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Maths Puzzle
Two water taps together fill a tank in 9 3/8 hours.the tap of larger diameter takes 10 hours less than the smaller one to fill the tank separately. find the time in which each tap can separately fill the tank.
Read Solution (Total 1)
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- Larger tap fill in = 15hrs
Smaller tap fill in = 25hrs
Let x = No. of hours required to fill by longer tap.
So, x+10 = No. of hours required to fill by smaller tap.
And v = Volume of the tank.
Portion of tank fill in 1hr by longer tap = v/x
Portion of tank fill in 1hr by smaller tap = v/x+10
Portion of tank fill in 1hr by both tap = v/(75/8)
v/x + v/(x+10) = v/(75/8)
1/x + 1/(x+10) = 8/75
75(2x+10) = 8(x^2 +10x)
150x+750 = 8x^2 + 80x
8x^2 - 150x + 80x -750 = 0
8x^2 - 70x - 750 = 0
By simplifying,
4x^2 - 35x - 375 = 0
(i.e) b^2 -4ac = 7225>0
x = 35+(square root (7225)) /8 (or) x = 35 - (square root (7225)) /8
x = (35+85) /8
x = 120/8
[x = 15hrs] and [x+10 = 15+10 = 25hrs].
Therefore,
Larger tap can fill in = 15hrs
Smaller tap can fill in= 25hrs - 12 years agoHelpfull: Yes(6) No(1)
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