Question

Which of the following numbers would have digit 9 at unit place? * 49² 94² 39² 73²

Answer 1

73 square alone have 9 in its unit place

Answer 2

To see the unit place we have to find the square of the unit digit.

i) 9^2 = 81; 49^2 does not have 9 at unit digit.

ii)4^2 = 16; 94^2 does not have 9 at unit digit.

iii)9^2 = 81; 39^2 does not have 9 at unit digit.

iv)3^2 = 9; 73^2 has 9 at unit digit.