Elena's Daughter sold 84 boxes, 84 boxes are 5% of the number of boxes the troop sold.
There are couple ways to solve this problem, here's how
I would do it:
84 = 5%
1% = ?
1% =
= 16.8
100% = 16.8 × 100
100% = 1680
The troop sold 1640 boxes of girl scout cookies.