Question

5+4+2=110 ,5+5+2=120 ,7+5+1=130 ,8+6+1=?

Answer 1

(5+4+2)* 10 = 110
similarly (5+5+2)*10 = 120 and (7+5+1)*10 = 130

Therefore,
(8+6+1)*10 = 150

Answer 2

The first step to solve such question is to look for patterns. You have to look if they're being added, subtracted, multiplied or divided. 

In this case, It is evident that all of these are being multiplied by 10 in order to get the result. For e.g.-

(5+4+2)*10=110
(5+5+2)*10=120
(7+5+1)*10=130

Hence, Continuing the pattern we get-

(8+6+1)*10=150

The answer is 150

I hope this is clear to you now! :)