Question

Practice Time
• There are $60$ mangoes. $\frac{1}{2}$ of them are ripe. How many mangoes are ripe?
• There are $32$ children. $\frac{1}{2}$ of them are girls. How many children are boys?
• There are $20$ stars. A quarter of them are red. How many stars are red?
How many are not red?
• Ravi wants a pencil. It costs $Rs.2.$ He gives a one-rupee coin, one half-rupee coin, and one quarter-rupee coin. Is it enough?

Answer 1

A) Total mangoes $=60$

$\frac{1}{2}$ of them are ripe.

Number of ripe mangoes $=60\times \frac{1}{2}=30$

$30$ out of $60$ mangoes are ripe.

B) Total children = 32

$\frac{1}{2}$ of them are girls.

So, $\frac{1}{2}$ of them are boys.

Number of boys $=32\times \frac{1}{2}=16$

$16$ out of $32$ children are boys.

C) Total stars $=20$

A quarter of them is red, which means $\frac{1}{4}$ of them are red.

Number of stars that are red $=20\times \frac{1}{4}=5$

$5$ out of $20$ stars are red.

Number of stars that are not red $=20-5=15$

D) Cost of a pencil $=Rs.2$

Money given by Ravi $=Rs(1+0.50+0.25)=Rs.1.75$ [$\because$ Half rupee coin$=Rs.0.5,$ a quarter rupee coin $=Rs.0.25$]

But, the pencil is for $Rs.2.$

Money required $=Rs.(2.00-1.75)=Rs.0.25$

Ravi did not give enough money to buy the pencil. $Rs.0.25$ more is required to buy the pencil.