Question

5 x 30. Draw a model to show your answer

Answer 1

We need to draw a model to compute this multiplication:

(1)
`5 * 30`

If we do the following transformation the result remains equal:

(2)
`5 * (5+5+5+5+5+5)`

Because:

(3)
`5+5+5+5+5+5=30`

Thus, by applying distributive property in (2):


`5 * 5+5 * 5+5 * 5+5 * 5+5 * 5+5 * 5`

There are 6 terms of
`5 * 5`.

Therefore we will compute:


`5 * 5=5+5+5+5+5=25`

Finally this result must be added to itself 6 times, that is:


`5 * 30=25+25+25+25+25+25=\boxed{150}`