Chapter 9: Halves and Quarters

Answer: The shaded part shows 1/4 part of the cake, which Raju has got.

Answer: The total cake together Rajni and Raju got is 3/4

NCERT book Page No: 99

Answer: Cost of 1/4 pumpkin = Rs. 10

Cost of one pumpkin = Rs 10 ÷ 1/4

= 10 × 4

= 40

Hence, the cost of one pumpkin = Rs. 40.

Answer: The cost of half a pumpkin = Rs. 10

So, the cost of full pumpkin = Rs. 10 + Rs. 10

= Rs. 20

Therefore, the cost of one full pumpkin is Rs. 20.

NCERT Book Page No: 100

Using a Price List

Answer: The cost of 1 kg tomato = Rs. 8

Hence, the cost of 1/2 kg tomato = Rs. 8 / 2

= Rs. 4

Therefore, the cost of 1/2 kg tomatoes = Rs. 4

(b) Which costs more – 1/2 kg of onions or 1/4 kg of carrots?

Answer: The cost of 1 kg onion = Rs. 10

Therefore, the cost of 1/2 kg onion = 10 / 2

= Rs. 5

The cost of 1 kg carrot = Rs. 16

Hence, the cost of 1/4 kg carrot = 16 / 4

= Rs. 4

Hence, the cost of 1/2 kg of onions is more than the cost of 1/4 kg of carrots.

(c) What is the price of 3/4 kg of potatoes?

Answer: The cost of 1 kg of potatoes = Rs. 12

The cost of 3/4 kg of potatoes = Rs. 12 × 3/4

= Rs. 36/4

= Rs. 9

Therefore, the cost of 3/4 kg of potatoes = Rs. 9

(d) Keerthi is going for shopping. She has only Rs. 20 with her. Can she buy all the things on her shopping list?

Answer: Total money Keerthi has = Rs. 20

Her shopping list includes = 1/2 kg potatoes, 2 kg pumpkin and 1/4 kg carrots.

Cost of 1 kg potatoes = Rs. 12

Cost of 1/2 kg potatoes = Rs. 12 / 2

= 6

Cost of 1 kg pumpkin = Rs. 4

Cost of 2 kg pumpkin = Rs. 4 × 2

= Rs. 8

Cost of 1 kg carrot = Rs. 16

Cost of 1/4 kg carrot = Rs. 16/4

= Rs. 4

Total cost of all the vegetables = 6 + 8 + 4

= Rs. 18

Hence, Keerthi can buy all the vegetables on her shopping list.

NCERT Book Page No: 101-103

Practice Time

(b) Colour that part of the shape which is written below.

(c) Cut in half

Draw a line which divides the below shapes into half.

(d) Colour half the number of shapes as shown here.

(e) Colour 1/4 of these shapes.

(f) Match the coloured part as shown.

(g) Make the other half

1/2 of the picture is drawn here. Can you complete the picture by drawing the other half?

(h) This is a quarter of a picture. Can you complete it? How many more quarters will you draw to complete it?

To complete the picture, three more quarters are required.

i.e, half and a quarter of a metre

Using your metre scale, cut a string of one metre.

On this string, mark the length 1/2 metre, 1/4 metre and 3/4 metre.

Using your string, draw a line of length ½ metre on the floor.

Answer: We know

1 m = 100 cm

1/2 m on the floor = 100 cm ÷ 2

= 50 cm

Hence, 1/2 m on the floor = 50 cm long

1/2 metre = 100 × 1/2

= 50 cm

1/4 metre = 100 × 1/4

= 25 cm

3/4 metre = 100 × 3/4

= 75 cm

Now, adding 1/2 and 1/4, we get

1/2 + 1/4 = (2 + 1)/4

= 3/4

Hence, on adding 1/2 and 1/4, we get 3/4.

NCERT Book Page No: 104

Sharing Milk

A bottle is full of milk, and it holds one litre. The milk is put into 4 other bottles so that each bottle has 1/4 litre of milk.

The shaded portion shows the level of milk marked in the figure given below

We know,

1 litre = 1000 millimetres

Each bottle contains = 1/4 litre of milk

Hence, each bottle contains = 1000 mL ÷ 4

= 250 mL of milk.