Question

The cost of hiring a chainsaw is 10$ plus an amount that is proportional to the square of the number of hours for which the chainsaw is hired. If it costs $32.50 to hire the chainsaw for 3 hours, find to the nearest half hour, the length of time for which the chainsaw was hired if the cost of hire was $60.

Answer 1

c=10+kh^2
Now you know that
10+9k=32.50
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