Question

What must be subtracted from each term
of the ratio 3:7, so that the ratio becomes
2:5? ?
​

Answer 1

$\underline{\bf{\purple{GIVEN:-}}}$

• If a number subtracted from ratio 3:7, then the ratio becomes 2:5.

$\underline{\bf{\purple{TO \: FIND:-}}}$

• The subtracted number.

$\underline{\bf{\purple{SOLUTION :-}}}$

Let the unknown number be x.

Now, according to question, we have to subtract the number 'x' from both the numerator and denominator of ratio 3:7.

$\sf\longmapsto \: \dfrac{3 - x}{7 -x } = \dfrac{2}{5} \\ \\ \sf\longmapsto \: 5(3 - x) = 2(7 - x) \\ \\ \sf\longmapsto 15 - 5x = 14 - 2x \\ \\ \sf\longmapsto 3x = 1 \\ \\ \sf\longmapsto \boxed{\boxed{ \bf{x = \dfrac{1}{3}}}}$

Therefore, if 1/3 is subtracted from each term of the ratio 3:7, the ratio becomes 2:5.