To divide fractions, you flip the denominator and then multiply it by the numerator.
-6 / 5 x (-25 / 3)
Multiply straight across; the negative cancels out.
150 / 15
This can be reduced to 15, which is its simplest form.
It would take 5 yrs. for both trees to be the same height.
Combine costs
59.99(3) + 75 = 179.97 + 75
179.97 + 75 = $254.99 (total cost)
Now add tax: 8% = 0.08
254.99 * 0.08 = 20.3992
254.99 + 20.3992 = 275.3892
Solution: bill would be around $275