The average of 4 terms is 30 and the 1st term is 1/3 of the sum of the remaining terms. What is the first term?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e 30
Let the first term be x, then the sum of the rest of the three terms is 3x.
Average = Sum of observations / Number of observations
⇒ 30 = (x + 3x) / 4
⇒ 120 = 4x
⇒ x = 30