Advertisements
Advertisements
Question
Using prime factorization, find the HCF and LCM of 21, 28, 36, 45 .
Solution
21 = 3 × 7
28 = 2 × 2 × 7 = 22 × 7
36 = 2 × 2 × 3 × 3 = 22 × 32
45 = 5 × 3 × 3 = 5 × 32
HCF = product of smallest power of each common prime factor in the numbers = 1
LCM = product of greatest power of each prime factor involved in the numbers
= 22 × 32 × 5 × 7 = 1260
APPEARS IN
RELATED QUESTIONS
Prove that the square of any positive integer of the form 5q + 1 is of the same form.
Define HOE of two positive integers and find the HCF of the following pair of numbers:
56 and 88
Define HOE of two positive integers and find the HCF of the following pair of numbers:
240 and 6552
Find the least number which when divides 35, 56 and 91 leaves the same remainder 7 in each case.
Without actual division, show that each of the following rational numbers is a terminating decimal. Express each in decimal form.
(i) `23/(2^3 × 5^2)`
Express each of the following integers as a product of its prime factors:
468
Express each of the following integers as a product of its prime factors:
945
Prove that following numbers are irrationals:
The HCF of 95 and 152, is
The smallest rational number by which \[\frac{1}{3}\] should be multiplied so that its decimal expansion terminates after one place of decimal, is
