Answer:

Step-by-step explanation:
The systems of equations are
Let us assume the rate of the current be c
Now actual speed against the current is (15 - c)
And, the actual speed with the current is (15 + c)
Here we applied the time formula i.e. distance by speed
Also the upstream time - downstream time = 4
Now the equations are

B if you’re doing distributive property
Someone better come get her because she dancing like a s.t.i.p.p.e.r
It is 9 because I think It is equaltion to 9
Given the amount of water needed to fill the cement dam and the water pump rate, the time needed to fill the dam is 400 minutes or 6hours 40minutes.
Option B)6h 40min is the correct answer.
<h3>How long does it take to fill the dam?</h3>
Given that;
- Amount of water needed to fill the dam A = 30000 litres
- Pump rate r = 75 litres per minute
- Time needed to fill the dam T = ?
To determine how long it take to fill the dam, we say;
Time need = Amount of water needed ÷ Pump rate
T = A ÷ r
T = 30000 litres ÷ 75 litres/minute
T = 400 minutes
Note that; 60min = 1hrs
Hence,
T = 6hours 40minutes
Given the amount of water needed to fill the cement dam and the water pump rate, the time needed to fill the dam is 400 minutes or 6hours 40minutes.
Option B)6h 40min is the correct answer.
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