Questions :
If the unit digit of (433 × 456 × 43N) is (N + 2), then what is the value of N ?
Options :
- 2
- 3
- 4
- 6
correct answer: d)
Unit’s digit of 433 × 456 = 8
Unit’s digit of 8 × 43N = N + 2
Clearly, N × 2 = 8
N = 8 – 2 = 6
(∴ Unit’s digit of 8 × 6 = 8)