The sum of 3 non zero prime numbers is 100 .One of them exceeds the other by 36 . Find the largest number ?
Let x , x + 36 and y are the three prime numbers.
According to the given condition,
x + x +36 + y = 100
⇒ 2x + y = 64 ..................(1)
Since x is a prime number, then 2x will be an even number.
Also addition of two even numbers results in an even number,
∴ from equation (1),we can conclude that y must be an even prime number.
⇒ y = 2 , as " 2 " is the only even prime number.
Put y = 2 in equation (1), we get
2x + 2 = 64 ⇒ x = 31
So the required prime numbers are 31, 31+36, 2 or 31, 67 and 2