Question

If a:b = 4:1, then find (a - 3b) / (2a - b)? a. 1/7 b. 3/7 c. 5/7 d. 2/7

Answer 1

Step-by-step explanation:

option a) 1/7 is correct answer..

Answer 2

(a-3b)/(2a-b) =1/7

Explanation:

Given:

a:b = 4:1

To find:

(a - 3b) / (2a - b)

Method 1: We can write the ratio in fraction,

==> a:b = 4:1

==> a/b = 4/1

==> a=4

==> b=1

==> Substitute a and b in the given equation

==> (a-3b)/(2a-b)

==> (4-3(1))/(2(4)-1)

==> (4-3)/(8-1)

==>  1/7

==> a)1/7

(a-3b)/(2a-b) =1/7

Method:2

==> a:b = 4:1

==> a/b =4/1

==> a = 4b

Substitute the a value in the given equation

==>  (a-3b)/(2a-b)

==> (4b-3b)/(2(4b)-b)

==> 1b/(8b-b)

==> 1b/7b

==> b gets cancel

==> 1/7

(a-3b)/(2a-b) = 1/7