Question

What will be the units digit of the squares of the following numbers?
(i) 52
(ii) 977
(iii) 4583
(iv) 78367
(v) 52698
(vi) 99880
(vii) 12796
(viii) 55555
(ix) 53924

Answer 1

The units digit is affected only by the last digit of the number. Hence, for each question, we only need to examine the square of its last digit.
(i) Its last digit is 2. Hence, the units digit is 2², which is equal to 4.
(ii) Its last digit is 7. Hence, the units digit is the last digit of 49 (49 = 7²), which is 9.
(iii) Its last digit is 3. Hence, the units digit is 3², which is equal to 9.
(iv) Its last digit is 7. Hence, the units digit is the last digit of 49 (49 = 7²), which is 9.
(v) Its last digit is 8. Hence, the units digit is the last digit of 64 (64 = 8²), which is 4.
(vi) Its last digit is 0. Hence, the units digit is 0², which is equal to 0.
(vii) Its last digit is 6. Hence, the units digit is the last digit of 36 (36 = 6²), which is 6.
(viii) Its last digit is 5. Hence, the units digit is the last digit of 25 (25 = 5²), which is 5.
(ix) Its last digit is 4. Hence, the units digit is the last digit of 16 (16 = 4²), which is 6.