How do you evaluate #-3\cdot \frac { 3} { - 8} \cdot \frac { - 2} { 7}#?

1 Answer

#-9/28#

Explanation:

Let's first put that first #-3# into a fractional form to help keep our numerators and denominators straight:

#-3/1xx3/(-8)xx(-2)/7#

Let's do the negative signs first.

Here's the thing:

#-1/2=(-1)/2=1/(-2)#

It doesn't matter where the negative sign is in the fraction - if there is one negative sign, the fraction is negative. In our question, there are three fractions, all of which are negative, and so we have:

#(-1)xx(-1)xx(-1)=-1# - our answer is going to be negative.

Now we can focus on the fractions themselves:

#3/1xx3/8xx2/7#

Let's cancel where we can:

#3/1xx3/cancel8^4xxcancel2/7=9/28#

Let's not forget that negative sign! So the final answer is #-9/28#