Question

The average of 4 numbers is 35 if first three numbers are 29 , 36 and 33 . Find the fourth number. *

Answer 1

let, the number be 29,36,33, a

29+36+33+a/4=35

98+a=140

a=42

therefore the fourth number is 42

Answer 2

✬ Fourth Number = 42 ✬

Given:

• Average of four numbers is 35.
• First three numbers are 29, 36 and 33.

To Find:

• What is the fourth number ?

Solution: Let the fourth number be x.

[ Average : The sum of all numbers of a set divided the the quantity of the number there ]

Here,

• Quantity of numbers = 4

➟ Average = (Sum of given numbers + x/4)

$\implies{\rm }$ 35 = 29 + 36 + 33 + x/4

$\implies{\rm }$ 35 = 98 + x/4

$\implies{\rm }$ 35 $\times$ 4 = 98 + x

$\implies{\rm }$ 140 = 98 + x

$\implies{\rm }$ 140 – 98 = x

$\implies{\rm }$ 42 = x

Hence, the fourth number is 42.

______________________

★ Verification ★

=> 35 = 29 + 36 + 33 + 42/4

=> 35 = 140/4

=> 35 = 35

$\large\boxed{\texttt{Verified}}$