Answer:
1/15
Step-by-step explanation:
The first thing to do is to change both denominators so that they're the same. In this case, that would be 15.
Then, whatever you do to the denominator, you must also do to the numerator.
+ x = 
X = 1/15
Answer:
x^-2
Step-by-step explanation:
(x*x*x)/(x*x*x*x*x)
1/x*x
1/x^2
x^-2
Answer:
120
Step-by-step explanation:
If order doesn't matter, there are 10 ways to chose the first ride, 9 ways to choose the second, and 8 ways to choose the third. This product (720) has you riding the same 3 coasters in 6 different orders. Dividing by 6 gives ...
720/6 = 120 different combinations of roller coasters
_____
This number might be written as 10C3 (choose 3 from 10). The meaning of that notation is ...
nCk = n!/(k!(n-k)!)
10C3 = 10!/(3!·7!) = 10·9·8/(3·2·1) = 120