Challenger App

No.1 PSC Learning App

1M+ Downloads
Of the 3 numbers whose average is 70, the first is 1/9 times the sum of other 2. The first number is:

A32

B21

C14

D42

Answer:

B. 21

Read Explanation:

Let the three numbers = a,b and c a+b+c = 70x3 = 210 .....(1) and a=1/9 × (b+c) => b+c = 9a put b+c =9a in equation (i), we get a+9a = 210 10a=210 a=21 first number = 21


Related Questions:

The sum of 10 numbers is 276. Find their average.
The average of 11 results is 60. If the average of the first 6 results is 59 and that of the last six is 62. Find the sixth result?
Calculate the average of the cubes of first 5 natural numbers
The average mark of 10 students in the class is 30 and average mark scored by all other students in the class is 40 if the total number of students are 30. Find the average of the whole class ?
A batsman has completed 15 innings and his average is 22 runs. How many runs must he make in his next innings so as to raise his average to 26?