1.

If the overall average of first 20 multiples of two numbers is 924, what is the average of the two numbers?1). 762). 443). 884). 80

Answer»

LET the numbers be ‘X’ and ‘y’

Sum of first 20 multiples of x = x(1 + 2 + … + 20) = (x × 20 × 21)/2 = 210x

Sum of first 20 multiples of y = y(1 + 2 + … + 20) = (y × 20 × 21)/2 = 210y

Their average = (210x + 210y)/40

⇒ 924 = 21(x + y)/4

⇒ x + y = 176

∴ Average of the two numbers = (x + y)/2 = 176/2 = 88


Discussion

No Comment Found

Related InterviewSolutions