sachin is younger than rahul by 9 years . if the ratio of their ages is 7 : 9 , find the age of sachin
"if rahul age is x , then sachin age is x - 9 , so ( x - 9 ) / x = 7 / 9 = > 9 x - 81 = 7 x = > 2 x = 81 = > x = 40.5 so sachin age is 40.5 - 9 = 31.5 answer : a"
multiply(divide(9, subtract(9, 7)), 7)