Solution.
Initial cost = c
Increase in cost = $3.49
New cost = $9.84
(a) The equation that represent the situation is
c + 3.49 = 9.84
(b) We want to solve c + 3.49 = 9.84
c + 3.49 = 9.84
subtract 3.49 from both sides
c = 9.84 - 3.49
c = 6.35
(C) The solution to the equation represent the original cost of the toy. This means the original cost of the toy is $6.35