This is esay to do when you realize the the speed of mowing is addtive. This is if John mows at 1 lawn / (2/3) hour and Gerge mows at 1 lawn / 1hour, the total speed of mowing is:
1 / (2/3) + 1 = 3/2 + 1 = 5/2
=> 5/2 of lawn per hour
Now, the time is calcualted as the amount of lawn divided by the speed:
1 lawn / (5/2 lawn/hour) = 2/5 hour.
Answer: 2/5 of an hour.
I don't think you need answer for that you already did it.
You could use many methods to find the answer to this problem, but I am going to use the most efficient one I know.
18f+15(4f)=156
F is for fins. We should now solve the equation.
18f+60f=156
78f=156
156÷78=2
So fins cost 2 dollars. Now, we know snorkels cost four times the amount of fins. Four times 2 is eight. So the snorkels cost $8 to rent. Let's check our math.
15(8) + 18(2)
120+36=156
So it cost $8 to rent a snorkel.
N^2 should be the correct answer. Based on those numbers, it appears that the sum can be found by squaring the term n
Assuming the price of the pool does not change, then
Additional interest required is 4500-3750=750
using
I=Pit, we set up equation
750=3750*0.055*t
Solve for t
t=750/(3750*0.055)=3.64 years.
So will need to wait 3.64 years, or rounded up to 4 years.