The number of possible combinations is given by
... C(18, 3) = 18!/(3!(18-3)!) = 18·17·16/(3·2·1) = 816 . . . . possible combinations
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There are 18 ways to choose the first one; 17 ways to choose the second one, and 16 ways to choose the 3rd one. The same 3 students can be chosen in any of 3! = 6 different orders, so the product 18·17·16 must be divided by 6 to get the number of possible combinations in which order doesn't matter.
Answer: x=3
Explain:
7x=21
21/7
Get you
3
So x equals 3
All you can do to this expression is simplify.
You need to combine all "like terms." There are two q terms so you need to combine those. To combine "like terms", simply add their coefficients. 6q has a coefficient of 6 and q has a coefficient of 1. So:

Therefore your end result is:
Answer:
This depends on the situation. For context, you use less than when your inequality CANNOT exceed more than.
You would use less than or equal to if your inequality can be equal to a number. Here's an example.
John needs to buy X oranges and Y apples. He can AT MOST buy 10 total fruits.
x + y (equal to or less than) 45
John needs to buy X oranges and Y apples. He CANNOT buy more than 10 total fruits.
x + y < 45
Answer:
f'(1x) = 2x
or
f'(0) = 4
Step-by-step explanation:
Hope this helps if not im sorry