Oliver, Tom and Warren bought some puffs. After Oliver ate ⁵₇ of his puffs, Tom ate ⁴₅ of his puffs and Warren ate 9 puffs, each of them had the same number of puffs left. Oliver had 18 less puffs than Tom at first.

1. How many puffs did Oliver have at first?
2. How many puffs did the 3 of them buy altogether? 

	Oliver	Tom	Warren
Before	7 u	5x2 = 10 u	2 u + 9
Change	- 5 u	- 4x2 = - 8 u	- 9
After	2 u	1x2 = 2 u	2 u

(a)
The number of puffs that Oliver and Tom each had in the end is the same. Make the number of puffs that Oliver and Tom each had in the end the same.  LCM of 2 and 1 is 2.

Number of puffs that Oliver had less than Tom at first
= 10 u - 7 u
= 3 u

3 u = 18

1 u = 18 ÷ 3 = 6

Number of puffs that Oliver had at first
= 7 u
= 7 x 6
= 42 

(b)
Total number of puffs that the 3 of them bought
= 7 u + 10 u + 2 u + 9
= 19 u + 9
= 19 x 6 + 9
= 114 + 9
= 123

Answer(s): (a) 42; (b) 123