Question

How so you multiply `\frac { 3} { 8} \times \frac { 16} { 21}`?

Answer 1

`2/7`

Explanation:

When multiplying fractions we look for any `color(blue)"common factors"` on the numerators / denominators that we can `color(blue)"cancel",` that is divide by.

Here 3 and 21 have a common factor of 3 and 8 and 16 have common factors of 2 , 4 and 8. We choose the highest common factor in this case 8.

`rArr3/8xx16/21=cancel(3)^1/cancel(8)^1xxcancel(16)^2/cancel(21)^7`

`=(1xx2)/(1xx7)=2/7larr" in simplest form"`

A fraction is in `color(blue)"simplest form"` when no other factor but 1 will divide into the both the numerator and denominator.