A = 245, B = 196, C = 140. B = 4/5 A; C = 4/7 A A + B + C = 581 = A + 4/5 A + 4/7 A = 2.37A => A = 245
A, B, C and D are four positive numbers such that A is 2/3 times of B, B is 5/6 times of C and C is 3/5 times of D. If the average of 3 times of A and 4 times of D is 900, then what is the average of all four numbers A, B, C and D?
Three non negative numbers A, B and C are such that the mean is X and the median is 7. If X is 12 more than the smallest number and 17 less than the biggest number. Find the value of A + B + C.
Square ABCD is inscribed in a quarter circle O such that B and C are on the arc of the quarter circle. If the quarter circle has a radius equal to 1, what is the area of the square?
Give positive numbers a, b and c are such that ab + bc + ca + abc = 4, What is the value of 1/a+2 + 1/b+2 + 1/c+2 = ?