A and B can do a work in 12 days, B and C in 15 days, C and A in 20 days. In how many days will they finish it together

A shopkeeper mixes 20 kgs of rice which cost Rs. 5 per kg with 35 kg of rice which cost Rs. 7 per kg. Then he sells the mixture at Rs. 6.50 per kg. Find his profit percentage.

HCF of 3240, 3600 and a third number is 36 and their LCM is 2⁴×3⁵×5²×7². The third number is

The sum of the ages of a son and father is 72 years. After 12 years the age of the father will be 3 times that of the son. What is the age of the son now

The population of a village is 50000, 40% of them are men, 35% of them are women and the rest are children. Find the number of children

If the price of an item is increased by 30% and then decreased by 30%. The final price compared to original price is