The harmonic mean H of two numbers is 4 and the arithmetic mean A and geometric mean G satisfy the
equation 2A + G^2 = 27. The two numbers are
(a) 6, 3 (b) 9, 5 (c) 12, 7 (d) 3, 1
The difference between a two-digit number and the number obtained by interchanging the digits is 36. What is the difference between the sum and the difference of the digits of the number if the ratio between the digits of the number is 1 : 2 ?