Question

What should be added to ((1/2) + (1/3) + (1/5)) to get 3?

Answer 1

Given ((1/2) + (1/3) + (1/5))
Let the required number be x
((1/2) + (1/3) + (1/5)) + x = 3
x = 3 - ((1/2) + (1/3) + (1/5))
LCM of 2, 3 and 5 is 30
Consider (1/2) = (1/2) $\times$ (15/15) = (15/30)
(1/3) = (1/3) $\times$ (10/10) = (10/30)
(1/5) = (1/5) $\times$ (6/6) = (6/30)
On substituting
x = 3 - ((15/30) + (10/30) + (6/30))
x = 3 - (31/30)
Now, 3 = (3/1) = (3/1) $\times$ (30/30) = (90/30)
Therefore,
x = 3 - (31/30) becomes,
x = (90/30) - (31/30)
x = (90 - 31)/30
x = (59/30)