###
**Of four numbers whose average is 60, the first is one-fourth of the sum of the last three. The first number is –
**

A. 15
B. 42
C. 45
D. 48
**Answer: Option D**

## Show Answer

Solution(By Apex Team)

Let the four numbers be a, b, c and d respectively
Then,
$\begin{array}{l}\text{⇒ a =}\frac{1}{4}\text{(b + c + d)}\\
\text{⇒ b + c + d = 4a}\\
\text{Also,}\\
\text{a + b + c + d = 60 × 4 = 240}\\
\text{⇒ a + 4a = 240}\\
\text{⇒ 5a = 240}\\
\text{⇒ a = 48}\\
\text{Hence, first number = 48}\end{array}$

## Related Questions On Average

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### If the arithmetic mean of 0, 5, 4, 3 is a, that of -1, 0, 1, 5, 4, 3 is b and that of 5, 4, 3 is c, then the relation between a, b, and c is.

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