# Squares and Square Roots-Class 8.

**Chapter 6 of NCERT/CBSE Class 8 Mathematics is about Squares and Square roots. Here in this lesson you can find out practice problems for this chapter.**

**CBSE CLASS 8 MATHEMATICS.Squares and Square Roots – Chapter 6/ Model Questions.Fill in the blanks:**

- A perfect square does not end with —-, —-, —– or —- at unit’s place.
- If a number has 1 or 9 in the unit’s place, then its square ends in —-
- What will be the one’s digit in the square of 1234?
- The number of zeroes in the square of 100 is —–
- Square numbers can only have ——- number of zeros at the end.
**Answer the following:** - What will be the unit digit of the squares of the following numbers?

a) 5432

b) 87960 - The following numbers are obviously not perfect squares. Give reason.

a) 2087

b) 54000 - State whether the square of given numbers is even or odd?

a) 432

B) 769 - Find the square root of 121 by the method of repeated subtraction.
- Express

a) 25 as the sum of 5 odd numbers.

b) 100 as the sum of 10 odd numbers.

**ANSWERS:**

- 2, 3, 7 or 8.
- 1
- 6
- 4
- Even
- a) 4

b) 0 - a) 2087 is not a perfect square, because it ends with 7. A perfect square does not end with 7 at unit’s place.

b) 54000 is not a perfect square because square numbers can only have even number of zeros at the end. - a) The square of 432 is even.

b) The square of 769 is odd. - To find the square root of 121:

121 – 1 = 120

120 – 3 = 117

117 – 5 = 112

112 – 7 = 105

105 – 9 = 96

96 – 11 = 85

85 – 13 = 72

72 – 15 = 57

57 – 17 = 40

40 – 19 = 21

21 – 21 = 0

From 121 we have subtracted successive odd numbers starting from 1 and obtained 0 at 11 th step. Therefore, square root of 121 is 11. - a) 1 + 3 + 5 + 7 + 9

b) 1 + 3+ 5 +7 + 9+ 11 + 13 + 15 + 17 + 19.