1100 stickers are in 3 bags.
The 3rd bag has 800 stickers more than the total number of stickers in the 2nd and 1st bags.
The 1st bag has 4 times as many stickers as the 2nd bag.
How many stickers does the 3rd bag contain?
Choose the bag with the least stickers to be 1 u.

Number of stickers in the 2nd bag = 1 u
Number of stickers in the 1st bag = 4 u

Number of stickers in the 2nd bag and 1st bag
= 1 u + 4 u
= 5 u

Number of stickers in the 3rd bag = 5 u + 800

Total number of stickers
= 1 u + 4 u + 5 u + 800
= 10 u + 800

10 u + 800 = 1100
10 u = 1100 - 800
10 u = 300

1 u = 300 ÷ 10 = 30

Number of stickers in the 3rd bag
= 5 u + 800
= 5 x 30 + 800
= 150 + 800
= 950

Answer(s): 950