Dylan, Oscar and Perry bought some wafers. After Dylan ate ³₇ of his wafers, Oscar ate ⁴₅ of his wafers and Perry ate 11 wafers, each of them had the same number of wafers left. Dylan had 78 less wafers than Oscar at first.

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

	Dylan	Oscar	Perry
Before	7 u	5x4 = 20 u	4 u + 11
Change	- 3 u	- 4x4 = - 16 u	- 11
After	4 u	1x4 = 4 u	4 u

(a)
The number of wafers that Dylan and Oscar each had in the end is the same. Make the number of wafers that Dylan and Oscar each had in the end the same.  LCM of 4 and 1 is 4.

Number of wafers that Dylan had less than Oscar at first
= 20 u - 7 u
= 13 u

13 u = 78

1 u = 78 ÷ 13 = 6

Number of wafers that Dylan had at first
= 7 u
= 7 x 6
= 42 

(b)
Total number of wafers that the 3 of them bought
= 7 u + 20 u + 4 u + 11
= 31 u + 11
= 31 x 6 + 11
= 186 + 11
= 197

Answer(s): (a) 42; (b) 197