(hope this helps can I pls have brainlist (crown) ☺️)
Step-by-step explanation:
7 does not occur in 1000. So we have to count the number of times it appears between 1 and 999. Any number between 1 and 999 can be expressed in the form of xyz where 0 < x, y, z < 9. You have 1 × 9 × 9 = 81 such numbers.
