Y + R + V = 42
but 4 YEARS AGO : (R-4) +(V-4) = Y
Replace Y in the 1st equation by: (R-4) +(V-4)
(R-4) +(V-4) + R + V = 42
2R - 2V - 8 = 42; 2R -2V = 50, or R+V=25
IF R+V =25 AND Y + R +V = 42, then Y + 25 = 42 and Y =17
The second one 2(2x) +2(4x+3)
The key words you should notice when looking at this word problem are “less than.” This means that the order is flipped, so “3 less than k” means “k minus 3.”
The expression for the ratio is k-3:k+3
Hope this helps