Question

Of the three numbers, the first number is twice the second number and the second number is twice the third number. The average of all three numbers is 21. The smallest of the three numbers is (2) 6 (1) 9​

Answer 1

Answer:

9

Step-by-step explanation:

Let the third number be x. Then,

2nd number = twice of x = 2x

1st number = twice of 2x = 4x

Average = (sum of observations)/number

Here, sum of all no. = 4x + 2x + x = 7x

number of term = 3

Thus,

=> 21 = (7x)/3

=> (21 × 3)/7 = x

=> 9 = x

As x is the smallest in x & 2x & 4x, value of smallest one is 9

Answer 2

Answer:

Let the third numer=x

The second number =2x

And the first number is=4x

According to the question,

(x+2x+4x)/3=21

=x+2x+4x=21*3=63

=7x=63

=x=63/7=9

Hence,the smallest number is 9