Chapter 5 - Exercise 5.3 - Prime Time provides a thorough understanding of Highest Common Factor (HCF) and Lowest Common Multiple (LCM). HCF and LCM problems come up often in many different maths topics, including fractions and number sequences.
These solutions are created in accordance with the NCERT and CBSE syllabus and will provide an understanding of the steps for finding HCF and LCM of two or more numbers with simple methods.
The provided NCERT Solutions for all questions in Exercise 5.3 are clearly and simply explained in a step by step manner. Practicing these exercises will allow you to be prepared for tests and classwork. You can also download the free PDF for quick revision.
The solutions for Exercise 5.3 use the latest NCERT syllabus and provide a clear and simple step-by-step method. Download the free PDF from below:
Which of the following pairs of numbers are co-prime? (a) 18 and 35 (b) 15 and 37 (c) 30 and 415 (d) 17 and 69 (e) 81 and 18 Sol. (a) Here factors of and factors of No common factor other than 1 . Hence 18 and 35 are co-prime numbers. (b) We have factors of and factors of No common factor other than 1 . Hence 15 and 37 are co-prime numbers. (c) Given numbers are 30 and 415 Here factors of and factors Clearly 5 is a common factor of 30 and 415 . Hence 30 and 415 are not co-prime numbers. (d) Here factors of and factors of No common factor other than 1 . Hence 17 and 69 are co-prime numbers. (e) Here factors of and factors of Clearly 9 is a common factor of 81 and 18. Hence 81 and 18 are not coprime numbers.
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