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Number System — Quantitative Aptitude Questions & Practice

Practise 56 Number System questions from Quantitative Aptitude for competitive exams such as UPSC, Banking, SSC and Railway. Read the worked questions below, check every answer with an explanation, and track what you get wrong.

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Practice questions on Number System — with answers

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1. What is the HCF (Highest Common Factor) of 12 and 18?

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Answer: A

Factorizing 12 and 18, their highest common factor is 6.

2. What is the LCM (Lowest Common Multiple) of 12 and 18?

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Answer: B

LCM of 12 and 18 = (12 x 18) / HCF(12,18) = (12x18)/6 = 36.

3. What is the HCF (Highest Common Factor) of 15 and 20?

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Answer: B

Factorizing 15 and 20, their highest common factor is 5.

4. What is the LCM (Lowest Common Multiple) of 15 and 20?

A45
B80
C60
D120

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Answer: C

LCM of 15 and 20 = (15 x 20) / HCF(15,20) = (15x20)/5 = 60.

5. What is the HCF (Highest Common Factor) of 24 and 36?

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Answer: C

Factorizing 24 and 36, their highest common factor is 12.

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Number System — Quantitative Aptitude Questions & Practice

Practice questions on Number System — with answers

1. What is the HCF (Highest Common Factor) of 12 and 18?

2. What is the LCM (Lowest Common Multiple) of 12 and 18?

3. What is the HCF (Highest Common Factor) of 15 and 20?

4. What is the LCM (Lowest Common Multiple) of 15 and 20?

5. What is the HCF (Highest Common Factor) of 24 and 36?

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