Question
Pipe βAβ can fill a tank in 25 hours while pipe
βBβ can empty it in 30 hours. They were operated on alternate hours starting with pipe βAβ. Find the percentage of tank filled this way in 42 hours.Solution
Let the total capacity of tank be 150 units Efficiency of pipe βAβ = 150/25 = 6 units/hour Efficiency of pipe βBβ = 150/30 = 5 units/hour Tank filled in 2 hours = (6 β 5) = 1 units Therefore, tank filled in (2 Γ 21 = 42 hours) = 1 Γ 21 = 21 units Required percentage of tank filled = (21/150) Γ 100 = 14%
- If a ten-digit number 57a61395z2 is divisible by 72, then find the number of possible values of βaβ.

- Ajayβs income is Rs. 50000. He spent Rs. 15000 less than the amount he managed to save. Find the percentage of income he used for expenses.
Find the Sum of all the even Factors of β240β
There are two numbers A and B such that when 24 times of B is added to 192, then result is equal to 336, and sum of A and B is 28, then what is the diff...
- A list contains nine consecutive even numbers. If the smallest number is 16% less than the largest one, what is the sum of the second smallest and the seco...
- A number exceeds 40 times its reciprocal by 7/8. Determine the number.
Find the sum of all natural numbers less than 500 which are divisible by 7.
Β How many numbers up to 800 are divisible by both 3 and 5?
0! +1! +2! +3!........+98! What will be the remainder when divided by 5?