Question

How do you solve `\frac{ 1}{ 10} = \frac{ 1}{ 60} + \frac{ 1}{ r }`?

Answer 1

`r=12`

Explanation:

Isolate `1/r" by subtracting " 1/60" from both sides"`

`1/10-1/60=cancel(1/60)cancel(-1/60)+1/r`

`(6xx1)/(6xx10)-1/60=1/r`

`rArr6/60-1/60=1/r`

`rArr5/60=1/rrArrcancel(5)^1/cancel(60)^(12)=1/r`

`" Thus " 1/12=1/r`

Since the fractions are equal and both have 1 in the numerator, then their denominators must be equal.

`rArrr=12" is the solution"`