Ben, David and Cody bought some croissants. After Ben ate ³₇ of his croissants, David ate ⁴₅ of his croissants and Cody ate 8 croissants, each of them had the same number of croissants left. Ben had 78 less croissants than David at first.

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

	Ben	David	Cody
Before	7 u	5x4 = 20 u	4 u + 8
Change	- 3 u	- 4x4 = - 16 u	- 8
After	4 u	1x4 = 4 u	4 u

(a)
The number of croissants that Ben and David each had in the end is the same. Make the number of croissants that Ben and David each had in the end the same.  LCM of 4 and 1 is 4.

Number of croissants that Ben had less than David at first
= 20 u - 7 u
= 13 u

13 u = 78

1 u = 78 ÷ 13 = 6

Number of croissants that Ben had at first
= 7 u
= 7 x 6
= 42 

(b)
Total number of croissants that the 3 of them bought
= 7 u + 20 u + 4 u + 8
= 31 u + 8
= 31 x 6 + 8
= 186 + 8
= 194

Answer(s): (a) 42; (b) 194