Question
Two pipes P and Q can fill a tank in 48 minutes and 64
minutes respectively. If both the pipes are opened simultaneously, after how much time Q should be closed so that the tank is full in 36 minutes?Solution
Let Q be closed after x minutes. Then, Part filled by (P+Q) in x min. + part filled by P in (36 – x ) min. = 1 x(1/48 + 1/64) + (36 - x) x 1/48 = 1 ⟹(7x/192) + (36 - x)/48 = 1 ⟹ 7x + 4 (36 – x ) = 192 ∴ x = 16 ∴ Hence, Q must be closed after 16 minutes
Determine the sum of the first 16 odd numbers.
For which range of 'p' does the expression 19p - 2p²- 35 have a positive value??
The remainder obtained when (47³ + 35³) is divided by 41 isÂ
16Â Â Â Â Â Â Â Â Â Â 4Â Â Â Â Â Â Â Â Â Â Â Â Â 2Â Â Â Â Â Â Â Â Â Â Â Â Â 1.5Â Â Â Â Â Â Â Â Â 1Â Â Â Â Â Â Â Â Â Â Â Â Â 1.875
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Find the unit digit of (76101 - 6).
Find the sum of all natural numbers less than 1,000 that are divisible by both 3 and 5 but not by 7.
How many times I write digit ‘1’ in first hundred natural numbers?Â
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