We must find UNIQUE combinations because choosing a,b,c,d... is the same as d,c,b,a...etc. For this type of problem you use the "n choose k" formula...
n!/(k!(n-k)!), n=total number of choices available, k=number of choices made..
In this case:
20!/(10!(20-10)!)
20!/(10!*10!)
184756
Answer:
its 43
Step-by-step explanation:
as x was 1 in the first problem
you add X (1) by 42 and get
43..
sorry if thats wrong.
Answer:
THE ANSWER WOULD BE TRUE MY FRIEND
h= number of hours
m= number of miles
Formula: 4h=12m
(4 hours equals 12 miles)
Divide 4 on each side.
h= 3m
3 miles per hour.
Then, convert miles to feet. And hours to minute.
To do this simultaneously,
Convert miles to feet and hours to minutes.
There should be 3 "fractions" to multiply.
The first should be the original problem:
3miles/1 hour. (3 miles per hour).
The second should be 1 hour/60min. (1 hour per 60 min).
The third should be 5280 ft/1 mile. (5280 feet per mile).
The second and the third fractions are to convert miles to feet and the hours to minutes.
A is the answer have a nice day