Add 2 digits to a multiple of 10 (timed)
Add a 2-digit number to a multiple of 10, speed challenge.
Add 2 digits to a multiple of 10 (timed)
Add a 2-digit number to a multiple of 10, speed challenge.

Add a 2-digit number to a multiple of 10, speed challenge.
Add a 2-digit number to a multiple of 10, speed challenge.