When a positive integer n is divided by 5 the remainder is 2. What is the remainder when the number 3n is is divided by 5 ?

In a two - digit number, the digit at the unit's place is 1 less than twice the digit at the ten's place. If the digits at units and ten's place are interchanged, the difference between the new and the original number is less than the original number by 20. The original number is: 

The mean of the first 7 prime numbers is:

The third proportional of two numbers 9 and  24 is

The mean of 20 items is 55. If two items 45 and 30 are removed, what will be the new mean of the remaining items?

Find the difference between mean and median in the given data 2.5, 4.6, 7.2, 3.3, 4.9, 5.6, 2.7?

If two numbers are each divided by the same divisor, the remainders are respectively 3 and 4. If the sum of the two numbers be divided by the same divisor, the remainder is 2. The divisor is 

If the sum of a number and its reciprocal be 2, then the number is-