Learn to add 35 + 27 thinking about place value. This example requires regrouping.
Addition within 100 is a free educational video by Khan Academy.It helps students in grades 2 practice the following standards 2.NBT.B.5.
1. 2.NBT.B.5 : Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction..