How many times does the digit 7 appear among the terms of the sequence of consecutive integer numbers 7, 8, 9, ...., 777?
Accepted Solution
A:
Answer:234 timesStep-by-step explanation:Number of times the number 7 appears in a hundred7 as units digit (07-17-27 ..... 97): 10 times7 as tens digit (70-71-72..... 79): 10 times20 times the digit 7 appears in first one hundred (0-100)Let's calculate how many times 7 would be as units or tens in 7 hundreds20X7 = 140 times digit 7 appears until number 699Now, from 700 to 7777 as hundreds digit (700-701-702 .... 777): 78 times7 as tens digit (770-771-772 .... 777): 8 times7 as units digit (707-717-727....777): 8 times78 + 8 + 8 = 94 times the digit 7 appears in the range 700 - 777. Plus 140 times 140 + 94 = 234 times