Question

How do you solve `\frac { 7b - 4} { b } = \frac { 9} { 7}`?

Answer 1

`b = 7/10`

Explanation:

We have,

`color(white)(xxx)(7b - 4)/(b) = 9/7`

`rArr 7(7b -4) = 9b` [Cross-multiplication]

`rArr 49b - 28 = 9b`

`rArr49b - 9b = 28` [Transpose the `b` terms to L.H.S]

`rArr 40b = 28`

`rArr b = cancel28^7/cancel40^10` [Dividing both sides by `40`]

`rArr b = 7/10`

Hope This helps.