Q.1. Fill in the blanks :
(a)
(b) (–3)3 × (–3)4 = ....................
View AnswerAns.
(a) 4
(b) (–3)7
Q.2. Evaluate :
(a) Find the value of x :
(b) Find the value of a :
View Answer
Ans. (a)
11-3 = 2x + 2
8 = 2x + 2
6 = 2x
x = 3
(b)
24 =a + 1
a = 23
Q.3. Match of column :
View Answer
Ans.
Column 'A' (Column 'B'
(a) (v)
(b) (iv)
(c) (i)
(d) (iii)
(e) (ii)
Q.4. Write in the standard form :
(a) The distance between Earth and Moon is 384,000 km.
(b) Speed of light in vacuum is 300,000,000 m/s
(c) 0.0034256
Ans. (a) 3.84 × 105 km
(b) 3 × 108 m/s
(c) 3.4256 × 10–3
Q.5. Find the value of x :
(a)
(b)
View AnswerAns. (a) Comparing power we get
2/5 = x
(b)
6-(-3) + 14 = x
9 + 14 = x
x = 23
Q.6. Simplify :
(a)
(b)
View AnswerAns.
(a)
(2/3)2 = 4/9
so after canceling (2/3)2 and 4/9
it would be 1/(4/7)2
49/16 would be final answer
(b)
10 = 5x 2
in numerator it would 54 and in denominator 53x23
5t4/8
Q.7. Simplify :
(a) (–3)2 × (–5)2
(b) [(-16)3 ÷ (-16)6 ] x (-16)3
View AnswerAns. (a) as power are same so base should multiply
(-3 x - 5 )2
225
(b) [(-16)3 ÷ (-16)6 ] x (-16)3
[(-16)6 ÷ (-16)3 ] = (-16)3-6=16-3
(-16)-3x (-16)3 = (-16)-3+3= 160=1
Q.8. Find the value of :
(a) 20 × 30 × 40
(b) 30 × 50 + 190
(c) (70 ÷ 30) × (80 – 50)
(d) 40× 60 + 1000
Ans. According to the property of exponents, any number raised to the power of zero equals one. [a0 = 1]
(a) 1 x 1 x 1 = 1
(b) 1 x 1 + 1 = 2
(c) (1÷1 ) x (1-1) = 1 x 0 = 0
(d) 1 x 1 + 1 = 2
Q.9. Fill in the blanks :
View Answer
Ans.
Q.10. Simplify and write the answer in scientific notation : (a) (5 × 103) × (3 × 105)
(b)
View AnswerAns.(a) (5 × 103) × (3 × 105)
15 x 108
1.5 x 109
(b)
= 4.5 x 10/0.9
= .5 x 10
= 5
Q.11. Find m for the following :
(a)
(b)
View AnswerAns. (a) 95 will get cancel out
85= 215 45 = 210
25= 2m
5 = m
(b)
73 will get cancel out from RHS and LHS
so only 2m= 23 so m = 3
m = 3
Q.12. Using the standard form, write number 73984 in expanded form.
View AnswerAns. 7 × 104 + 3 ×103 + 9 × 102 + 8 × 101 + 4 × 100
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1. What are exponents and how are they used in mathematical expressions? |
2. How do you simplify expressions involving exponents? |
3. What are the laws of exponents that I should know for my exam? |
4. What is the difference between positive and negative exponents? |
5. How do you evaluate expressions with fractional exponents? |
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