**“****How Heavy How Light****” **is **Chapter 12 **from **Merry Math IV **for students of** Class 4th **of **JKBOSE**. This particular post is about **How Heavy How Light ****Class 4 Math JKBOSE Solutions**. In a previous post, you read about **Tables and Shares ****Class 4 Math JKBOSE Solutions. **Let’s get started:

**How Heavy How Light ****Class 4 Math JKBOSE Solutions**

**Page No 161 – 162 Solutions**

Salim and Javaid were shifting the house. They loaded all their things on a horse-cart. There were many things like a water tank, five sacks of wheat, three tables, an almirah, four chairs, two mattresses, three sacks of rice, a bamboo ladder, pots and pans.

When they were ready to move, the horse refused to start. They wondered why. Their father said that this horse was not well and would not pull a load heavier than 700 kg. Oh! But how heavy is this load? —they asked.

Father gave them some idea of the weight of each thing.

**Find out the total weight they had loaded on the cart.**

Sol. The total weight they had loaded in the cart is as under.

Things loaded | Weight | No. of items | Total weights |
---|---|---|---|

A sack of wheat | 100 kg | 5 | 5 × 100 = 500 kg |

A sack of rice | 35 kg | 3 | 3 × 35 = 105 kg |

Water tank | 50 kg | 1 | 1 × 50 = 50 kg |

Almirah | 70 kg | 1 | 1 × 70 = 70 kg |

A table | 10 kg | 3 | 3 × 10 = 30 kg |

A chair | 5 kg | 4 | 4 × 5 = 20 kg |

A mattress | 20 kg | 2 | 2 × 20 = 40 kg |

Bamboo ladder | 10 kg | 1 | 1 × 10 = 10 kg |

Pots and pans | 10 kg | 10 kg | |

Total weight | 835 kg |

Total weight of all the things loaded = 500 + 105 + 50 + 70 + 30 + 20 + 40 + 10 + 10 = 835 kg

Therefore, the total weight they had loaded on the cart was 835 kg.

Now they decided to remove a few things from the cart.

**Which things should be removed so that the weight of the load is not more than 700 kg?**

Ans. Total weight on the cart = 835 kg.

Weight on the cart a horse can pull = 700 kg.

Weight to be removed from the cart = 835 – 700 = 135 kg

Given from table.

Weight of 3 sacks of rice = 105 kg

Weight of 3 tables = 30 kg

Total weight o these things = 105 kg + 30 kg = 135 kg

So, 3 sacks of rice and 3 tables can be removed so that the weight of the load is not more than 700 kg.

**Now you also make your own balance. Write down how you made it. Also, draw a picture of your balance in the box below.**

Ans. Do it yourself

**Activity 1**

Salim and Javaid put a pencil and a geometry box in the two pans of the balance. Which pan will go down? Why? Draw a picture to show it.

**Ans: **The pan which has a geometry box will go down because the geometry box is heavier than a pencil.

**Page No 163 Solutions**

**What is the heaviest?**

**Make groups of three things. For example, ball and paper. Use the balance to arrange them in order of the lightest, the one with in-between weight, and the heaviest.**

**Complete the table with at least five examples.**

Ans.

Lightest | In-between Weight | Heaviest |
---|---|---|

Paper | Eraser | Bat |

Feather | Scarf | Bird |

Needle | Spoon | Laptop |

Handkerchief | Shirt | Jean Pant |

Pencil | Sack | Tent |

**Can you find your own weight using this balance?**

Ans. We cannot find our own weight using this balance.

**Page No 164 Solutions**

**Making Weights**

Get a new cake of soap. This packet will have the weight written on it. You can use this soap to make your own different weights.

**The soap weighs ____________ grams (g).**

Ans. The soap weighs** 75** grams (g)

Take a small plastic packet. Put it in one pan of the balance. Put the soap in the other pan.

Slowly add sand to the packet till the pans are balanced. Close the packet with a rubber band or string. **Now stick a strip of paper and write ____________ g on it.**

Ans. Now stick a strip of paper and write ** (75 g) **on it.

If you put the soap and the weight you just made together in a pan. **How many grams will both these weigh** **____________?**

Ans. The total weight of both of these will be 150 grams.

**Use your weights to weigh different things and write in your notebook.**

Ans. Do it Yourself

**Page No 165 Solutions**

**Practice Time**

**Which pan of the balance will go down? Show by drawing an arrow.**

Ans.

**Is the weight on any of the pans equal to 1 kilogram? Mark it.**

Ans. In the above pan, the weight is equal to 1 kilogram.

**How many grams are there in 1 kg?**

Ans. There are 1000 grams in 1 kg.

**Page No 166 Solutions**

**Grams and Kilograms**

**Name 5 things that we usually buy:**

Ans.

In grams | In Kilograms |
---|---|

1. Turmeric powder | 1. Sugar |

2. Pepper | 2. Vegetables |

3. Cloves | 3. Washing Powder |

4. Cardamom | 4. Rice |

5. Cashew | 5. Flour |

**Which is Heavier?**

**Which is heavier-1 kg cotton or 1 kg iron?**

Ans. If the volumes are the same Iron is heavier than cotton. But in weight 1 kg cotton and 1 kg iron both are equal.

**Page No 167 Solutions**

**Ahmad Went Shopping**

Ahmad went to a shop and bought some things. His younger brother cut the end of the bill where the weights were written.

**Guess and write the weight of each thing he bought in g or kg. **

Sol. The weight of each thing in g or kg, is shown in the table below:

Items | Weight |
---|---|

Rice | 5 kg |

Sugar | 1 kg |

Mustard seeds | 10 g |

Wheat | 3 kg |

Dal | 500 g |

Tea | 250 g |

Pepper | 25 g |

**Page No 169 Solutions**

**Car and Tractor**

Anjali is weighing her toys. She wants to know if her tractor is heavier than her car.

**How could you help her to find out quickly?**

Ans. This can be done by placing the tractor and car in each of the pans of the weighing balance separately. The pan with the toy which goes down is the heavier toy of these two.

**Guess which is the heaviest real car, a bus or a tractor?**

Ans. A bus is the heaviest among a real car, a tractor and a bus.

**Which is the heaviest thing you have seen?**

Ans. The heaviest thing I have seen is a road roller.

**Page No 173 – 175 Solutions**

**How Much the Chair Weighs**

**Anita wants to weigh this chair using the weighing machine. Can you suggest a way to do this?**

Ans. In a balance, find the equivalent weight of the chair by putting the chairs in one pan and stones in the other pan. Now put these stones on the platform of the weighing machine and see the reading. This gives the weight of the chair.

**Broken Stones**

Abdul sells firewood. There was a stone in his shop which weighed 13 kg. He used it to weigh firewood.

One day the stone fell down and broke into three pieces which weighed: 2 kg, 5 kg and 6 kg.

But Abdul was very smart. He used those three pieces to weigh firewood of all weight from -1 kg to 9 kg.

**Now you show how Abdul will use these stone pieces to weigh- **

**(A) 4 kg of firewood**

Ans: Abdul can place 6 kg stone in one pan and 2 kg stone along with firewood in another pan. Once the weights of both the pans are equal then he can say that the weight of the firewood is 4 kg.

4 kg firewood + 2 kg stone = 6 kg

**(B) 3 kg of firewood**

Ans: Abdul can place 5 kg of stones on one pan and 2 kg of stone along with firewood on the other pan. If the weight of both the pans is equal, he can say that the weight of firewood is 3kg.

3 kg of firewood + 2 kg stone = 5 kg stone

**(C) 7 kg of firewood**

Ans: Abdu can place 5 kg and 2 kg stones on one pan and firewood on the other pan. If both the pans become equal in weight, he can say that the firewood weighs 7 kg.

7 kg of firewood = 2 kg stone +5 kg stone

**Page No 176 Solutions**

**Post Office**

**Have you ever been to a post office?**

Ans. Ans. Yes, I have been to a post office.

**What different things do people go there for?**

Ans. People go there to post letters/ parcels, money orders, purchase postal items etc.

**How much does a postcard cost? **

Ans. A postcard costs 50 paise.

**How much does an inland letter cost?**

Ans. An inland letter costs ₹ 2.50.

**Look at the postal rates given in the chart in the book.**

**How much will you have to pay for stamps on a letter weighing 50 grams?**

Sol. Charges for 20 grams or less = ₹ 5.00

Charges for an additional 20 grams = ₹ 2.00

Charges for the next 10 grams = ₹ 2.00

Total charges for 50 grams = ₹ 9.00 Ans.

**Page No 176 Solutions**

**Waseem wants to send a parcel of the Merry Maths textbook to his friend Veena in Delhi. The book weighs 200 g. See the chart to find the cost of posting the book.**

Sol. Charges for parcels weighing 50 grams or less = ₹ 5.00

(Charges for additional 50 grams = ₹ 3.00)

So the charges for an additional 150 grams = ₹ 3 × 3.00 = ₹ 9.00

Total charges for parcel weighing 200 grams = ₹ 5.00 + ₹ 9.00 = ₹ 14.00

**How Many Stamps?**

**Iqbal needs stamps of Rupees 25 for his parcel. He went to the post office. Only stamps of ₹ 1, ₹ 2, ₹ 5 and ₹ 10 were there at that time. Using those stamps in how many different ways can he make ₹ 25?**

**Can you show five different ways? What is the heaviest parcel he can send using stamps of ₹ 25?**

Sol. The following different ways can make use of 25 for buying stamps.

(i) 25 stamps × ₹ 1 = 25 stamps in ₹ 25

(ii) 12 stamps × ₹ 2 + 1 stamp × ₹ 1 = 13 stamps in ₹ (24+1) = ₹ 25

(iii) 5 stamps × ₹ 5 = 5 stamps in ₹ 25

(iv) 2 stamps × ₹ 10 + 1 stamp × ₹ 5 = 3 stamps in ₹ (20+5) = ₹ 25

(v) 1 stamp × ₹ 10 + 1 stamp × ₹ 5+ 5 stamps × ₹ 2 = ₹ (10+ 5 + 10)= 7 stamps in ₹ 25.

The heaviest parcel that can be sent using 25 stamps is of weight :

We know

(Charges for 1st 50 grams = ₹ 5.00)

(Charges for additional 50 grams = ₹ 3.00)

So, 50 grams = ₹ 5.00

300 grams= (For next ₹ 18.00 at the rate of 3.00 for an additional 50 grams)

Total weight = 350 grams

**Page No 178 – 179 Solutions**

**Our Weight Together**

A frog was struggling to escape from the mouth of a crow. How can I escape? —the frog thought. Suddenly a trick came to his mind. He asked the crow-Are you good at arithmetic? If yes, then I will ask you a problem.

“Your weight is 650 g and I am only 145 g, how much do we weigh together?”

The crow was good, at mathematics, so he happily opened his beak to answer.

**What happened after that? So, what was the answer the crow wanted to give?**

Ans. When the crow opened his beak to give the answer, the frog jumped out from his beak and escaped. The answer was (650 +145) g = 795 grams.

**Am I Fit or Fat?**

The chart shows the height and weight of children between 6 and 10 years old.

**Now, you also fill the table by finding out the age, height and weight of any five friends**

Ans.

Note: You can also make your own chart.

**Page No 180 Solutions**

**Puzzle**

**How Many Oranges?**

All oranges have equal weight. The two papayas have the same weight. The weights in the first and second balances are equal.

**How many oranges balance the weight in the third?**

In the second balance:

Two papayas = Two oranges + one mango

2 papayas = 2 oranges + 1 mango

We know that all oranges have equal weight

So, in the first balance

1 mango + 1 orange = 3 oranges

1 mango + 1 orange – 3 oranges = 0

1 mango – 2 oranges = 0

1 mango = 2 oranges

And

In second balance

2 papayas = 2 oranges + 1mango (1 mango = 2 oranges)

2 papayas = 2 oranges + 2 oranges

2 papayas = 4 oranges

1 papaya = 4/2 oranges

1 papaya = 2 oranges

Now in the third balance:

One papaya + one mango = 2 oranges + 2 oranges

1 papaya + 1 mango = 4 oranges.

**Page No 181 Solutions**

**There are 3 marbles of the same size but one marble is slightly heavier or lighter than the other two. Can you | find which is that marble and if it is heavier or lighter? You can use a balance only two times.**

Ans. Take three marbles such that one of them is slightly heavier or lighter than the other two.

Now put one marble in one pan and the second marble in another pan.

See two situations arise:

**In the First situation.** If the two pans balance each other, then the third marble is either heavier or lighter. Now put the first marble in one pan and the third marble in another pan. If the position of the pan. containing the third marble goes down, then the third marble is heavier.

**In the Second situation.** Now put the second marble in one pan and the third marble in another pan. Now the position of the pan containing the first marble goes up, and then the first marble is lighter than the third marble.

In this way, we can find either the third marble is heavier or lighter than marble first and second.

**Now Try These- [Activity]-**

**Decide what would you use, kg or g, to measure the weight of the following objects:**

**(a) a wooden almirah**

**(b) a table**

**(c) a spoon**

**(d) a glass**

**(e) a book**

**(f) a tin full of oil **

**(g) a chalk stick **

**(h) a sack of rice.**

Sol. (a) kg (b) kg (c) g (d) g (e) g (f) kg (g) g (h) kg.

**Weigh the following object(s) rounding to the nearest 100 grams:**

**(a) a melon **

**(b) a brick**

**(c) 10 potatoes**

**(d) a packet of salt**

**(e) a mathematics books**

**(f) 10 match-boxes, each full of sticks**

**(g) a lemon**

**(h) a water bottle. **

Sol. Try yourself.

**If 1 kg of rice costs ₹ 20, find the cost of:**

**(a) 2 kg of rice **

Sol. Cost of 1 kg of rice = ₹ 20

Cost of 2 kg of rice = ₹ 2 × 20 = ₹ 40 Ans.

**(b) 4 kg of rice **

Sol. Cost of 1 kg of rice = ₹ 20

The cost of 4 kg of rice = ₹ 4 × 20 = ₹ 80 Ans.

**(c) 10 kg of rice **

Sol. Cost of 1 kg of rice = ₹ 20

Cost of 10 kg of rice = ₹ 10 × 20 = ₹ 200 Ans.

**(d) 500 g of rice**

Sol. 500 g = 500/1000 kg = ½ kg

Cost of ½ kg of rice = ₹ ½ × 20 = ₹ 10 Ans.

**(e) 200 g of rice **

Sol. 200 g = 200/1000 = ⅕ kg

Cost of 200 g of rice = ₹ ⅕ × 20 = ₹ 4 Ans.

**(f) 100 g of rice **

Sol. 100 g = 100/1000 kg = 1/10 kg

Cost of 100 g of rice = ₹ 1/10 × 20 = ₹ 2 Ans.

**(g) 400 g rice**

Sol. 400 g = 400/1000 kg = ⅖ kg

Cost of 400 g of rice = ₹ ⅖ × 20 = ₹ 8 Ans.

**(h) 600 g of rice.**

Sol. 600 g = 600/1000 kg = ⅗ kg

Cost of 600 g of rice = ₹ ⅗ × 20 = ₹ 12 Ans.

**The cost of 100 g of cashew nuts is 50. Find the cost of cashew nuts weighing:**

**(a) 200 g**

Sol. Cost of 100 g of cashew nuts = ₹ 50

Cost of 200 g of cashew nuts = ₹ 50/100 × 200 = ₹ 100

**(b) 500 g**

Sol. Cost of 100 g of cashew nuts = ₹ 50

Cost of 500 g of cashew nuts = ₹ 50/100 × 500 = ₹ 250 Ans.

**(c) 1 kg**

Sol. Cost of 100 g of cashew nuts = ₹ 50

Cost of 1 kg of cashew nuts = ₹ 50/100 × 1000 = ₹ 500 Ans.

**(d) 50 g.**

Sol. Cost of 100 g of cashew nuts = ₹ 50

Cost of 50 g of cashew nuts = ₹ 50/100 × 50 = ₹ 25 Ans.

That’s it about **How Heavy How Light ****Class 4 Math JKBOSE Solutions. **Hope you found it useful. Do share your views about this post in the comment section below.

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