Jane = j
Andre = a
Maria = m
Andre picks 3 times as many pounds as Maria
3m
Jane picks two times as many pounds as Andre
2a
So:
j = 2a
a = 3m
m = 1m
The total weight is 840 pounds.
So: 2a + 3m + 1m = 840
Since a = 3m, replace the a in 2a with 3m : 2(3m)
2(3m) + 3m + 1m = 840
2(3m) = 6m [multiply 2 with 3]
6m + 3m + 1m = 840
Add all together
10m = 840
Divide 10 by both sides
m = 84
Since Maria picked 84 pounds and Andre picked 3 times the amount Maria picked, multiply 84 by 3 to get the final result.