Question

what should be subtracted from each term in the ratio 5 ratio 6 so that it becomes 8:11?

Answer 1

The number to be subtracted is "7"

See the attachment for the solution.

Answer 2

Firstly treat the ratios as fractions 6:5 to 6/5 and 11:15 as 11/15.

Let ‘x’ be the value you take from the terms 6 and 5.

The Equation then becomes (6 - x) / (5 -x) = 11/15

You get 15 (6 - x) = 11 (5 - x) by cross multiplying

Solve for ‘x’

90 - 15x = 55 - 11x

90 - 55 = 15x - 11x

35 = 4x results in x = 8.75 which is your answer

Substitute this in your equation above and you will see it equals 0.733333 which is the same as 11/15 the ratio 11:15.

Tip, remember when checking the equation a minus divided by a minus comes out positive!