How many times will the digit 7 be written when listing the integers from 1 to 1000?
Pick one.
A) 110  B) 111  C) 271  D) 300  E) 304
Another approach:   In the range 0-100:   7 as units digit - 10 times (7, 17, 27, ..., 97);   7 as tens digit - 10 time (71, 72, 73, ..., 79);   So in first one hundred numbers 7 is written 10+10= 
<gadget id="calculator">10+10</gadget>
<output>20</output>
20 times.   In 10 hundreds 7 as units or tens digit will be written  10*20= 
<gadget id="calculator"> 10*20</gadget>
<output>200</output>
200 times. Plus 100 times when 7 is written as hundreds digit (700, 701, 702, ..., 799).   Total 200+100= 
<gadget id="calculator">200+100</gadget>
<output>300</output>
300.   Answer: 300.
<result>D</result>
How many times will the digit 7 be written when listing the integers from 1 to 1000?