Page 72 - Start Up Mathematics_8 (Non CCE)

6. Find the square root by the long division method: (a) 3,136 (b) 19,321 (c) 695.9044
7. Find the square upto three places of decimal: (a) 42.7364 (b) 0.00984 (c) 2.304076

Thinking Skills

1. A square room having one side equal to 12 m is to be paved with square tiles of side 50 cm. What is the
number of tiles required to pave the room?
2. Neha walks from her house 160 m north and from there 630 m west to visit her friend’s house. While
coming back, she walks diagonally from her friend’s house to her house. How much distance does she
cover while returning?
3. Two buildings are 20 m and 25 m high. If they are 12 m apart, find the distance between their tops.
4. Aditya was flying a kite which was at a height of 40 m just above a tree. The string was 50 m long. How
far away from the tree was Aditya flying the kite?
5. A square area in front of Hariti’s house is converted into a park. She spent ` 1,76,400 at the rate of
` 25 per square metre. What is the length of each side of the park?
6. Complete the grid and find the squares of the following numbers:
(a) 278 (b) 315
2 7 8 3 1 5
1 1
2 3
4 9
1 5 0 0
7 1
4 6 3 1
5
8 5
6 5 5

Values and Life Skills

A school collected ` 1,22,500 as donation for leprosy patients from the students. If each student paid as many
rupees as there were students, how many students are there in the school? Doing charity is our social responsibility.
Justify this statement.
Some NCERT Textbook Questions

1. The following numbers are obviously not perfect squares. Give reason.
(i) 1057 (ii) 23453 (iii) 7928 (iv) 222222
(v) 64000 (vi) 89722 (vii) 222000 (viii) 505050

2. (i) Express 49 as the sum of 7 odd numbers.
(ii) Express 121 as the sum of 11 odd numbers.
3. Write a Pythagorean triplet whose one member is
(i) 6 (ii) 14 (iii) 16 (iv) 18
4. For each of the following numbers, find the smallest whole number by which it should be multiplied so
as to get a perfect square number. Also find the square root of the square number so obtained.
(i) 252 (ii) 180 (iii) 1008 (iv) 2028
(v) 1458 (vi) 768
5. The students of Class VIII of a school donated ` 2401 in all, for Prime Minister’s National Relief Fund.
Each student donated as many rupees as the number of students in the class. Find the number of students
in the class.

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