Download Class-VIII Math Assignment Chapter Rational Numbers, Squares

Class-VIII
Math Assignment
Chapter Rational Numbers, Squares and square roots and Cubes and cube roots
1. Find using appropriate properties:
3 x -4_ 4 5 x 3
8
7 21 7
8
2. Verify that –(- x )=x for: (i) x =3
(ii) x= -14
41
23
3. Represent -5 , -8 and -13 on a number line.
9 9
9
4. Find eight rational numbers between 3 and 4
7
7
5. Write the additive and the multiplicative inverses of each of the following rational numbers:
a) 2
b) -3
c) -9
9
4
6. Name the property for each of the following:
a) (-3 ) x 2= 2 x (-3 )
b) 1 x 1 x 1 = 1x 1 x 1
2
3 3
2
2
4
8
2 4 8
7. Find ten rational numbers between -1 and 2
5
3
8. Write any five rational numbers each greater than -3
9. Fill in the blanks:
(i)
The rational number which is equal to its additive inverse is ______________
(ii)
The product of a rational number and its multiplicative inverse is always _________
(iii)
Every negative rational number is ______________than zero.
10. Find the square of following numbers without actual multiplication: (i) 53 (ii) 79
11. Find a Pythagorean triplet in which one number is (i) 20
(ii) 18
12. Find the square root of the following numbers through prime factorization.
(i) 1296
(ii) 2704
(iii) 5625
13. Find the square root of the following numbers by division method.
(i) 401956
(ii) 998001
(iii) 80.1025
14. Find the smallest number by which 32448 must be divided so that the quotient is a perfect
square. Find the square root of the quotient.
15. Find the smallest square number that is divisible by each of the numbers 6, 10 and 15.
16. There are 600 children in a school. For a PT drill, they have to stand in such a way that the
number of row is equal to the number of columns. How many children would be left out in
this arrangement?
17. Express 81 as the sum of 9 odd numbers.
18. How many numbers lie between squares of 14 and 15 ?
19. Find the smallest number by which the following numbers must be multiplied so that the
product is a perfect cube: (i) 231525
(ii) 222264
20. Find the smallest number by which the following numbers must be divided so that the
quotient is a perfect cube: (i) 574992
(ii) 189000