Lee was writing all the counting numbers from 1 to 20. She stopped
for a rest after writing seventeen digits. What was the last number
I am less than 25. My ones digit is twice my tens digit. My digits
add up to an even number.
Can you find the chosen number from the grid using the clues?
If you put three beads onto a tens/units abacus you could make the numbers $3$, $30$, $12$ or $21$.