Harry, Oliver and Tom bought some croissants. After Harry ate ⁵₇ of his croissants, Oliver ate ¹₂ of his croissants and Tom ate 2 croissants, each of them had the same number of croissants left. Harry had -36 less croissants than Oliver at first.

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

	Harry	Oliver	Tom
Before	7 u	2x2 = 4 u	2 u + 2
Change	- 5 u	- 1x2 = - 2 u	- 2
After	2 u	1x2 = 2 u	2 u

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

Number of croissants that Harry had less than Oliver at first
= 4 u - 7 u
= -3 u

-3 u = -36

1 u = -36 ÷ -3 = 12

Number of croissants that Harry had at first
= 7 u
= 7 x 12
= 84 

(b)
Total number of croissants that the 3 of them bought
= 7 u + 4 u + 2 u + 2
= 13 u + 2
= 13 x 12 + 2
= 156 + 2
= 158

Answer(s): (a) 84; (b) 158