Secondary School (English Medium) (5 to 8) Class 8 - CBSE Question Bank Solutions

If x² + y² = 29 and xy = 2, find the value of x + y.

If x² + y² = 29 and xy = 2, find the value of x - y.

Rohan can paint \[\frac{1}{3}\]  of a painting in 6 days. How many days will he take to complete the painting?

If x² + y² = 29 and xy = 2, find the value of x⁴ + y⁴ .

Anil can do a piece of work in 5 days and Ankur in 4 days. How long will they take to do the same work, if they work together?

Mohan takes 9 hours to mow a large lawn. He and Sohan together can mow it in 4 hours. How long will Sohan take to mow the lawn if he works alone?

Sita can finish typing a 100 page document in 9 hours. Mita in 6 hours and Rita in 12 hours. How long will they take to type a 100 page document if they work together?

A, B and C working together can do a piece of work in 8 hours. A alone can do it in 20 hours and B alone can do it in 24 hours. In how many hours will C alone do the same work?

A and B can do a piece of work in 18 days; B and C in 24 days and A and C in 36 days. In what time can they do it, all working together?

A and B can do a piece of work in 12 days; B and C in 15 days; C and A in 20 days. How much time will A alone take to finish the work?

A, B and C can reap a field in \[15\frac{3}{4}\] days; B, C and D in 14 days; C, D and A in 18 days; D, A and B in 21 days. In what time can A, B, C and D together reap it?

A and B can polish the floors of a building in 10 days. A alone can do \[\frac{1}{4}\] th of it in 12 days. In how many days can B alone polish the floor  ?

What must be added to the following expression to make it a whole square? 

4x² − 12x + 7

What must be added to the following expression to make it a whole square? 

4x² − 20x + 20

Convert the following percentage to fractions and ratio:
25%

Convert the following percentage to fractions and ratio:
2.5%

Convert the following percentage to fractions and ratio:

0.25%

Convert the following percentage to fractions and ratio:
0.3%

Convert the following percentage to fractions and ratio:
125%