Question
Three pipes A, B, and C can fill a tank in 15 hours, 20
hours, and 25 hours respectively. All three pipes are opened together, but after 4 hours, pipe C is closed. How much more time will it take to fill the tank completely?Solution
Calculate the combined rate of all three pipes (A, B, C):
Work done in the first 4 hours (all pipes open):
Remaining work:
Rate after closing pipe C (only A and B):
Time to complete remaining work:
The least number which when divided by 6, 7, 10, 13, and 15 leaves the same remainder 5 in each case, is:
What is the Highest Common Factor of 54, 162 and 270?
HCF of two numbers 60 and 100 can be expressed in the form of (20m – 120) whereas LCM of these two numbers can be expressed in the form of (40n – 20...
Two men started moving in a circular path from the same place at the same time in the same direction. If they complete one revolution in 12 min and 16 m...
Two numbers are in the ratio 5:12, and their least common multiple (LCM) is 1,440. Determine the sum of these two numbers.
The LCM of two natural numbers is 10 times their HCF. If the product of given two numbers is 1000, then find the LCM of the numbers.
Find the greatest number of 4 digits divisible by 15, 25, 40 and 75.
The HCF of two numbers is 18 and their LCM is 540. If one of the numbers is 90, find the other number.
The HCF of two numbers is 9 and their LCM is 360. If one number is 45, find the other number.
