Two numbers are in the ratio 8 : 7. If we add 09 in each number then the ratio becomes 5 : 4. Find the least number.

42 35 24 21

21

1st :  2nd = 8 : 7 ATQ, ⇒ \(\frac{8R + 9}{7R + 9}\) = \(\frac{5}{4}\) ⇒ 32R + 36 = 35R + 45 ⇒ 3R = 9 1R = 3  So, Least No. = 7R = 7 × 3 = 21