This is the basic and conceptual question from real numbers in which we have to find the greatest possible length of each plank and also asked to find the number of planks formed by the three different lengths of plank 42m, 49m and 63m.

Kindly solve the above problem in detail

RS Aggarwal, Class 10, chapter 1B, question no 20

## Given : the lengths of three pieces of timber are 42 m,49 m and 63 m respectively. we have to divide the timber into equal length of planks.

greatest possible length of each plank =HCF(42,49,63)

The prime factorization of 42,49 and 63 are:

42=2×3×7

49=7×7

63=3×3×7

HCF (42,49,63)=7

the greatest possible length of each plank is 7 m.

again, the number of planks can be formed =22.