Question

If the hcf of 210 and 55 is expressible in the form 210 into 5 minus 55 y find y

Answer 1

Prime Factorization of 210 and 55

210 = 3*7*2*5

55 = 5*11

Therefore common factor is 5 implies HCF is 5

According to problem 210*5-55*y = 5

implies 210 - 11*y = 1 (dividing with 5 on both sides)

y = 209/11 = 19