Write an equation to represent the value of his stamp collection in terms of the number of stamps, s, that he had originally, and find the value of s.
Tony misplaced 7 stamps
Each stamp worth = $0.15
Total value of stamp now = $5.55
Let the number of stamps be 's'
Number of stamps now = s - 7 (misplaced 7 stamps)
price (number of stamps now ) = 0.55
0.15 (s - 7) = 5.55
Divide by 0.15 on both sides
s - 7 = 37
Add 7 on both sides
s = 44
Total number of stamps originally he had = 44 stamps