The table below shows the cost for a movie theater membership with an initial start up fee charged in the first month.

Question

Number of months/cost
1 / 55
2 / 90
3 / 125
The cost per month is?
The initial cost is?

Answer 1

To find the cost per month, we can calculate the difference in cost between each consecutive month and divide by the number of months:

Cost for 1 month: $55
Cost for 2 months: $90
Cost for 3 months: $125

Cost difference between 1st and 2nd month: $90 - $55 = $35
Cost difference between 2nd and 3rd month: $125 - $90 = $35

Average cost per month: ($35 + $35) / 2 months = $70 per month

To find the initial cost, we can subtract the cost per month from the first month's total cost:

Initial cost = Total cost for 1 month - (Cost per month x Number of months)
Initial cost = $55 - ($70 x 1) = $55 - $70 = -$15

Since it doesn't make sense to have a negative initial cost, we can conclude that there might be a mistake in the given data or calculations.