Video Transcript
Find the missing number.
This image shows us two things: the blue blocks represent nine times four and the green blocks represent nine plus nine plus nine plus nine. We know that nine times four is the same thing as adding nine to itself four times.
If we find out how many blocks there are in either the blue or the green, we can find the missing number. Our blue blocks have nine rows. We can start by labelling the first row one through nine. After that, we’ll have 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, and 36.
Nine times four equals 36, and that means nine plus nine plus nine plus nine equals 36. Our missing number is 36.
