Question

A copier at the high school has a counter which tallies how many copies have been made on the machine. The counter, however, has a glitch: it always skips the digit 4. For example, the counter will jump from 23 copies to 25 copies, or from 39 copies to 50 copies. If the counter currently reads 2005, how many copies has the machine actually made?

Answer 1

for every thousand, no 400's ... down to 1805

for every 100, no 40's ... down to 1625

for every 10, no 4's ... down to 1462

Answer 2

thx