Question 90215
Let x = 1st number
(x+2) = 2nd number
(x+4) = 3rd number

Since the question asks for the sum of twice the first number and the third number, we will add those two values.

(x+4)+2x=49
3x+4=49
3x+4-4=49-4
3x=45
x=15

So 2x = 30.  30 + your 3rd number(19) equals 49.

Good luck!