Page 35 - Start Up Mathematics_8 (Non CCE)

Some NCERT Textbook Questions

1  4   1  4
1. Tell what property allows you to compute ×  6 ×  as  × 6 × .

3  3   3  3
8 1
2. Is the multiplicative inverse of –1 ? Why or why not?
9 8
–2 –5 –9
3. Represent , , on the number line.
11 11 11
–2 1
4. Find ten rational numbers between and .
5 2

3 3
5. Find ten rational numbers between and .
5 4
Exemplar Problems

3  − 5  − 19
1. The numerical expression +   = shows that:
8  7  56
(a) rational numbers are closed under addition.
(b) rational numbers are not closed under addition.
(c) rational numbers closed under multiplication.

(d) addition of rational numbers is not commutative.
2. If y is the reciprocal of rational number x, then the reciprocal of y is:
x y
(a) x (b) y (c) (d)
y x
3. The negative of a negative rational number is always a ________ rational number.
–7
4. lies between –3 and –4. (True/False)
2
5. If x + y = 0, then –y is known as the negative of x, where x and y are rational numbers. (True/False)
1 1
6. of the class students are above average, are average and rest are below average. If there are
6 4
48 students in all, how many students are below average in the class?

1
7. Find two rational numbers whose absolute value is .
5
7 1
8. A skirt that is 35 cm long has a hem of 3 cm. How long will the skirt be if the hem is let down?
8 8

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