How do you solve \frac { w } { 3} + \frac { 2} { 5} = \frac { 1} { 15}?

1 Answer
Nov 19, 2016

w=-1

Explanation:

You need to find the (lowest) common denominator and since 3 and 5 are primes and 15=3 cdot 5 we have "LCD"(3,5,15)=15. We multiply both sides of the equation by 15:
15\cdot \frac { w } { 3} +15\cdot \frac { 2} { 5} =15\cdot \frac { 1} { 15}
5w+3 \cdot 2=1
5w+6=1
5w=1-6
5w=-5
w=-1