Answer: √5
2.7 is a rational number because it's a terminating decimal which means that the decimal does end and all terminating decimals are rational numbers.
-3 is a rational number because it's an
integer and all integers are rational.
√4 is rational because it's a perfect square which means that a number can be multiplied by itself to get 4 and that number is 2.
√5 is no rational! It's impossible to find a whole number multiplied by itself to give us 5 which means that it's
non-terminating and non-repeating.