Answer:
1,120
Step-by-step explanation:
We start off the multiples of 8 with 8, 16, 24, 32, 40, 48, 56, 64, 72, 80, 88, 96, 104
The smallest positive 2 digit multiple is 16
The smallest 3 digit multiple is 104
We know 8 x 100 = 800, so we are still in 3 digits
Now we try 8 X 110 = 880
Now let's try 8 x 120 = 960
Now, 8 x 125 = 1,000 which is the smallest 4 digit number we can get
16 + 104 + 1000 = 1,120