Answer: he has 32 numbers left.
Step-by-step explanation:
The first given number is 0.
1-digit number 1 *1 (=1)
2-digit numbers (1 and , 2 choices for 2nd digit). 1*2 (= 2)
3-digit numbers ( 1, 2 and first choice for 3.). 1*2*2 (= 4)
4-digit numbers (we join our answer for 1,2 and 3 with first choice of 4). 1*2*2*2 (= 8)
5-digit numbers s (1, 2, 3rd, 4th & first Choice of 5th digits). 1*2*2*2*2 (= 16)
Total number range from 0 to 1.
1 + 1 + 2 + 4 + 8 + 16
= 2^5
= 32.
