Given the expression:
we will find the sum by drawing place value block
See the following figure:
As shown in the figure:
At the place of hundreds, each square represents 100
At the place of tens, each rectangle represents 10
And at the place of ones, each small square represents 1
So, as shown for the number 245
We have two squares and 4 rectangles and 5 small squares
And for the number 137
We have 1 square, 3 rectangles and 7 small squares
To find the sum of the numbers, we will begin from the ones
5 + 7 will give 1 tens