25 of 100: Life, the Universe, and Everything
Number Theory
Level
2
The positive number \(\color{red}X\) is divisible by 42, and is composed of only 1s and 0s when written in base 10. What's the smallest number that \(\color{red}X\) might be?
If you don't know where to begin, take a peek at the divisibility rules on this page.
by
Jason Dyer