# Does anyone know how to solve the following Maths question on Volume (MHO would be selected)?

It is actually my nephew's homework and I am not sure how to help him.
Thanks a million for your kindness.

0|0
03

• Base areas:
A = 15 x 20 = 300cm^2
B = 18 x 20 = 360cm^2

Convert flow rates to change in water level:
A = 1.2L = 1200cm^2
-> 1200 / 300 = 4cm per minute

B = -0.72 = -720cm^2
-> -720 / 360 = -2cm per minute

Water level over time:
A: Ha = 0 + (T * 4)
B: Hb = 15 - (T * 2)

When both tanks are at the same level:
Ha = Hb
0 + (T * 4) = 15 - (T * 2)

T * 6 = 15

Divide each side by 6:
T = 15 / 6 = 2.5 minutes (or 150 seconds if you prefer)
THE ANSWER TO A IS 2.5 MINUTES

Plugging this back into one of the other equations:
Ha = 0 + (T * 4)
Ha = 0 + (2.5 * 4) = 10
THE ANSWER TO B IS 10CM

0|0
0|0
• Sorry - those flow rates should be in cubic centimeters, not square centimeters - 1200^cm3 and -720cm^3
And in case you weren't sure, an asterisk means multiply.
Although, I realize this is probably too late now anyway...