Answer:
40
Step-by-step explanation:
Let number of stickers Sophia has be "x" and number of stickers Ethan has be "y"
Now,
Sophia has 3 for every 2 ethan has, that means
3x = 2y
When sophia gives 16, she will have:
3x - 16
Ethan, after getting 16, will have:
2y + 16
This trade will make Ethan to have TWICE, so we can write:
2(3x-16) = 2y + 16
Now, the 1st equation can be written as:
3x = 2y
x = 2y/3
Now replacing this into 2nd, we solve for y:
So altogether they have:
24+16=40