Q3 of 55 Page 63

HCF of co-prime numbers 4 and 15 was found as follows by factorization: 4 = 2 × 2 and 15 = 3 × 5 since there is no common prime factor. So, HCF of 4 and 15 is 0. Is the answer correct? If not, what is the correct HCF?

No, the answer is not correct. 1 will be the correct HCF.


Explanation: The factorization of 4 and 15 is given as: 


4: 1 × 2 × 2


15: 1 × 3 × 5


Here, the highest common factor is 1.

More from this chapter

All 55 →
1

Find the HCF of the following numbers:

(a) 18, 48 (b) 30, 42


(c) 18, 60 (d) 27, 63


(e) 36, 84 (f) 34, 102


(g) 70, 105, 175


(h) 91, 112, 49 (i) 18, 54, 81


(j) 12. 45. 75

 2

What is the HCF of two consecutive-

(a) numbers?


(b) even numbers?


(c) odd numbers?

 1

Renu purchases two bags of fertiliser of weights 75 kg and 69 kg. Find the maximum value of weight which can measure the weight of the fertiliser exact number of times.

 2

Three boys step off together from the same spot. Their steps measure 63 cm, 70 cm and 77 cm respectively. What is the minimum distance each should cover so that all can cover the distance in complete steps?