Maharashtra Board Text books

Maharashtra Board Class 8 Math Chapter 1 Chapter 1 Rational and Irrational Numbers Practice Set 1.2 Solution

Question 1.
Compare the following numbers.
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Solution:
i. 7, -2
If a and b are positive numbers such that a < b, then -a > -b.
Since, 2 < 7 ∴ -2 > -7

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Here, the denominators of the given numbers are not the same.
LCM of 12 and 16 = 48
Maharashtra Board Class 8 Maths Solutions Chapter 1 Rational and Irrational Numbers Practice Set 1.2 1
Alternate method:
15 × 16 = 240
12 × 7 = 84
Since, 240 > 84
∴ 15 × 16 > 12 × 7
Maharashtra Board Class 8 Maths Solutions Chapter 1 Rational and Irrational Numbers Practice Set 1.2 2

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Here, the denominators of the given numbers are not the same.
LCM of 8 and 4 = 8
Maharashtra Board Class 8 Maths Solutions Chapter 1 Rational and Irrational Numbers Practice Set 1.2 3

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Here, the denominators of the given numbers are not the same.
LCM of 15 and 5 = 15
Maharashtra Board Class 8 Maths Solutions Chapter 1 Rational and Irrational Numbers Practice Set 1.2 4

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Here, the denominators of the given numbers are not the same.
LCM of 11 and 4 = 44
Maharashtra Board Class 8 Maths Solutions Chapter 1 Rational and Irrational Numbers Practice Set 1.2 5

Questions and Activities

Question 1.
Verify the following comparisons using a number line. (Textbook pg. no, .3)
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Solution:
Maharashtra Board Class 8 Maths Solutions Chapter 1 Rational and Irrational Numbers Practice Set 1.2 6
We know that, on a number line the number to the left is smaller than the other.
∴ 2 < 3 and -3 < -2
i.e. 2 < 3 and -2 > -3
Maharashtra Board Class 8 Maths Solutions Chapter 1 Rational and Irrational Numbers Practice Set 1.2 7