Base ten blocks (problem 10)

We have learnt that a child must learn the starting point before knowing the final point. Don't understand? Not to worry. Here's the sample of getting the total sum easily without much hassle.

An example of starting point:                  25 + 12 = ?

Let's take the 1st numbers                         2   + 1   = 3

Now take the second numbers                    5 +  2 = 7

3 and 7 makes 37 which is the total sum.