HCF AND LCM – EXERCISE 3.3.1 – Class 9

1. Find HCF and LCM of the following

(i) 9x²y²z³ and 15x³y²z⁴

Solution:

HCF = 3x²y²z³

LCM = 45x³y²z⁴

 

(ii) 8x⁴a² and 48x³b²

Solution:

8x⁴a² = 2³ x⁴ a²

48x³b² = 2⁴ x 3x³ b²

HCF = 8x²

LCM = 48x⁴ a² b⁴

 

(iii) 240 and 64x⁸

Solution:

240 = 2² x 3 x 5

64x⁸ = 2⁶ x x⁸

HCF = 2⁴ = 16

LCM = 2⁶ x 3 x 5 x x⁸ = 960x⁸

 

(iv) 2009b2y5 and 44 b⁴y³

Solution:

2009b2y5 = 7 x 41 x b²y5

44 b⁴y³ = 2² x 11b⁴y³

HCF = 2⁴ = b²y³

LCM = 2009 x 44 x b⁴y⁵

= 88396 b⁴ y⁵

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2. Find HCF and LCM of the following:

(i) p⁵ , p¹¹ , p⁷

Solution:

LCM = p⁵

HCF = p¹¹

 

(ii) 10 a²b²c² , 15ab²c³ , 20b³c²

Solution:

10 a²b²c² = 2 x 5a²b²c²

15 ab²c³ = 3 x 5 ab²c³

20 b³c² = 2² x 5 b³c²

LCM = 5 b²c²

HCF = 2² x 5 x 3 a²b³c³

= 60 a²b³c³

 

(iii) 4x³ , y³ , z³

Solution:

LCM = 1

HCF = 4x³y³z³

 

(iv) 24a⁵b⁵c⁴ , 30a³b⁴c³ , 36a²b³c⁵

Solution:

24 a⁵b⁵c⁴ = 2³ x 3 a⁵b⁵c⁴

30 a³b⁴c³ = 2 x 3 x 5 a³b⁴c³

36 a²b³c⁵ = 2² x 3² a²b³c⁵

LCM = 2 x 3a²b³c³

= 6 a²b³c³

HCF = 2² x 3² x 5 a⁵b⁵c⁵

= 360 a⁵b⁵c⁵

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HCF AND LCM – EXERCISE 3.3.1 – Class 9

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