What is the product in lowest terms?
-5/12 x 8/13
a.
-20/39
b.
-10/39
c.
-5/39
d.
3/25

-5/12 × 8/13

First, we need to start out by applying the multiplication rule towards fractions. If you haven't learned or don't remember the rules, you can always look up fraction rules. The rule is: a/b × c/d = ac/bd. Basically, we are combining the numerators and both of the denominators.


Second, let's now multiply what we have in the fraction. (5 × 8 = 40) and (12 × 13 = 156). Doing so will create a new fraction for us to use.


Third, now obviously, we can simplify the fraction we just got into lower terms. To do that, we have to collect the greatest common factor (GCF) of both the numerator and denominator and list their factors to find the common factor that is the greatest.

Factors of 40: 1, 2, 4, 5, 8, 10, 20, 40
Factors of 156: 1, 2, 3, 4, 6, 12, 13, 26, 39, 52, 78, 156

Out of the listed factors, which of those are the common ones? 1, 2, and 4 are the common factors. Since we are looking for the greatest common factor, it would be 4 since that is the higher number out of the commons. The GCF is 4.

Fourth, we can now divide our numerator (40) and our denominator (156) by the GCF we just found out, which was 4. 


Fifth, our last step is to create our new simplified fraction. All we have to do is take our new numerator and denominator to see the fraction. 

Answer in fraction form: 
Answer in decimal form: