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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


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