2.NBT.8 Mentally Add and Subtract Multiples of 10 & 100 Test Prep

2.NBT.8) Mentally add 10 or 100 to a given number 100–900, and mentally subtract 10 or 100 from a given number 100–900.

Addition
Add multiples of 10
Add multiples of 100

Subtraction
Subtract multiples of 10  
Subtract multiples of 100