8. Three times the square of a natural
numbers is 363. Find the numbers.
Sol. Let the
natural number be x,
As per the given
condition,
3x2 =
363
∴ x2 =
363/3
∴ x2 =
121
∴ x = ±√121
∴ x = ± 11
∵ x is a natural
number
∴ x cannot be negative
∴ x = 11
∴ The natural
number is 11.
