Question

The model bellow represents the expression 5x18 . How many tens will there be in in the final product

Answer 1

Consider the expression $5 \times 18$

Expanding 18 as (10+8),

= $5 \times (10+8)$

By using distributive property, we get

= $( 5 \times 10) + ( 5 \times 8)$

= 50 + 40

By adding, we get

= 90

The digit at units place is '0' and the digit at tens place is '9'.

Therefore, there are 9 tens in the final product of  $5 \times 18$.