SOLUTION: How would you do this problem: (-3/5)(-4/21)? It may seem simple but I'm not sure of the steps. Thanks!

Algebra ->  Numeric Fractions Calculators, Lesson and Practice -> SOLUTION: How would you do this problem: (-3/5)(-4/21)? It may seem simple but I'm not sure of the steps. Thanks!      Log On


   



Question 705939: How would you do this problem: (-3/5)(-4/21)? It may seem simple but I'm not sure of the steps.
Thanks!

Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
%28-3%2F5%29%28-4%2F21%29
First, you figure out if the product will have a minus sign.
If both factors have the same sign, the product is positive,
so no minus sign is needed.
%28-3%2F5%29%28-4%2F21%29=%283%2F5%29%284%2F21%29
Now, when we multiply fractions,
we multiply the numerators (the top parts) to get the numerator of the result,
and we multiply the denominators (the bottom parts) to get the denominator of the result.
%283%2F5%29%284%2F21%29=3%2A4%2F%285%2A21%29
At this point we see if we can simplify,
because it is easier to simplify at this point than afterwards.
21=3%2A7 so we can write it as that
3%2A4%2F%285%2A21%29=3%2A4%2F%285%2A3%2A7%29
Then we can cross out the 3's and end up with 4%2F5%2F7=highlight%284%2F35%29
because 3%2F3=1 and