MULTIPLYING FRACTIONS BY WHOLE NUMBERS

Example 1 :

Find the value of :

4 ⋅ 1/7

Solution :

4 ⋅ 1/7  =  (4 ⋅ 1)/7

4 ⋅ 1/7  =  4/7

Example 2 :

Find the value of :

1/4 of 2⅕

Solution :

1/4 of 2⅕  =  1/4 ⋅ 2⅕

1/4 of 2⅕  =  1/4 ⋅ 11/5

1/4 of 2⅕  =  (1 ⋅ 11)/(4 ⋅ 5)

1/4 of 2⅕  =  11/20

Example 3 :

In a group of 60 students 3/10 of the students like to study Science, 3/5 of the students to study Math.

(i) How many students like to study Science ?

(ii) How many students like to study Math ?

Solution :

(i)  Out of 60 students, 3/10 of the students like to study Math.

Then, the number of students who like to study Science is

=  3/10 of 60

=  3/10 ⋅ 60

=  (3 ⋅ 60)/10

=  (3 ⋅ 6)/1

=  18/1

=  18

(ii)  Out of 60 students, 3/5 of the students like to study Math.

Thus, the number of students who like to study Math is

=  3/5 of 60

=  3/5 ⋅ 60

=  (3 ⋅ 60)/5

=  (3 ⋅ 12)/1

=  36/1

= 36

Example 4 :

A car runs 20 miles using 1 liter of petrol. How much distance will it cover using 2 3/4 liters of petrol ?

Solution :

Distance covered in 1 liter of petrol is 20 miles.

Then, the distance covered using 2 3/4 liters of petrol is 

=  2¾ ⋅ 20 miles

=  11/4 ⋅ 20 miles

=  (11 ⋅ 20)/4 miles

= (11 ⋅ 5)/1 miles

=  55/1 miles

=  55 miles

So, the car can cover 55 miles of distance using 2 3/4 liters of petrol.

Kindly mail your feedback to v4formath@gmail.com

We always appreciate your feedback.