Answer: 3 miles per hour
<u>Step-by-step explanation:</u>
Use the formula "distance (d) = rate (r) x time (t)" to create a system of equations.
Let "r" represent the rate they are rowing
Let "c" represent the current
time rate distance <u>EQUATION</u>
Downstream: 4 hours r + c 40 miles 4(r + c) = 40
Upstream: 10 hours r - c 40 miles 10(r - c) = 40
Distribute, then eliminate r to solve for c:
Down: 4r + 4c = 40 → 5(4r + 4c = 40) → 20r + 20c = 200
Up: 10r - 10c = 40 → -2(10r - 10c = 40) → <u>-20r + 20c</u> =<u> -80</u>
40c = 120
<u> ÷40 </u> <u>÷40 </u>
c = 3
Answer:
answer : 10111
Step-by-step explanation:
Last month, my house used 1,740 kilowatt-hours of electrical energy,
and the part of my bill that charged for the electricity was $226.20 .
For the same month, my brother in Boston used 1,175 kilowatt-hours
of energy, and the energy part of HIS bill was $199.75 .
Which of us gets the better deal on his electrical energy ?
