There are two numbers such that the first number is half of the second number. If their average is 15, then what is the first number?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. 10.
Let the second number be 2x then, the first number be x
We know that,
Average = Sum of observations/Number of Observations
Now,
⇒ 15 = (x + 2x)/2
⇒ 30 = 3x
⇒ x = 10
This, the first number is 10