The answer is B. 120
nCr = n! / ((r! * (n - r)!)
n = 10
r = 3
10C3 = 10! / ((3! * (10 - 3)!)
= 10! / ((3! * 7!)
= (10 * 9 * 8 * 7 * 6 * 5 * 4 * 3 * 2 * 1) / (3 * 2 * 1 * 7 * 6 * 5 * 4 * 3 * 2 * 1)
= 3628800 / 30240
= 120
Answer:
+30 +-25
Savings is positive
Buying is negative
Step-by-step explanation:
+30 saved
-25 to buy
+30 +-25
Savings is positive
Buying is negative
OK , first you need to know that you can only add or subtract like variables
So you cant do 9x - 7i
Then 3 x 3x = 9x
The equation is solved as 7i greater than 7u