Class 7 Maths Chapter 2 Question Answers - Fractions and Decimals

Q1. Find:

Ans: Let us convert the mixed fractions to improper fractions and find the product by multiplying.

Converting 19/9 into mixed fractions, we get,

Converting 145 / 24 into mixed fractions, we get,


Q2. There are 45 students in a class and 3/5 of them are boys. How many girls are there in the class?
Ans: Known: Number of students in a class = 45
Fraction of boys in the class = 3/5
Unknown: 
To find how many girls are there in the class.
Steps:
Number of boys in the class  = 3/5 of 45
= 3/5 x 45
= 27
Number of boys in the class = 27
Number of girls = Total number of students − Number of boys in the class

= 45 - 27
= 18
Therefore, number of girls in the class = 18

Q3. The product of two numbers is  . If one of the numbers is  , find the other.
Ans:
We know that, Product of two numbers =
One of the numbers given =
Unknown: 
To find the other number. Let us consider the other number to be x .
Steps:

Converting the mixed fraction to improper fraction we get,

Taking the reciprocal of 19/3 we get,

Converting the improper fraction to mixed fraction we get,


Q4. A bus can cover 62.5 km in one hour. How much distance can it cover in 18 hours?
Ans: 
We know that,
Distance covered by the bus in 1 hour = 62.5 km

Unknown: 
Distance covered by bus in 18 hours
Therefore, the distance covered by bus in 18 hours is 1,125 km

Q5.  Shikha cuts 50 m of cloth into pieces of 1.25 m each. How many pieces does she get?
Ans: 
We know that,
Total length of the cloth Shikha has = 50 m
Length of each piece of the cloth after cutting = 1.25 m
Unknown: 
We should find the number of pieces obtained after cutting.
Steps:
Number of Pieces = Total length of the cloth / Length of each of the cloth
= 50 / 1.25
Convert the decimal to whole number and take the reciprocal,

= 50000 ÷ 125 = 40
Therefore, the number pieces obtained after cutting the cloth is 40