Quantitative Aptitude - Arithmetic Ability Questions

In a class of 39 students there are 26 girls. The average weight of these girls is 42 Kgs and average weight of the full class is 48 kgs. What is the average weight (in kgs) of the boys of the class?

Vikram and Vivek can finish a work in 50 days. They worked together for 20 days and then left. How much work has been done by them?

If xa+b+1=xa-b+a-ba+b, then x is equal to

If the product of two numbers is 2400 and their LCM is 96 then their HCF is

In each of the following questions two equations I and II are given. Solve both the equations and give answer:
$$\begin{gathered} I. x2+2x-195=0 \\ II. y2+30y+225=0 \end{gathered}$$

If the edge of a cube is increased by 10%, then what will be the percentage increase in its volume ?

The compound interest earned in two years at 12% per annum is Rs 10176. What is the sum (in Rs) invested?

What is the value of 1xp-q+1+1xq-p+1?