This is a combination in which you choose 4 from 10.
The formula is
combinations = 10! / 4! * (10-4)!
combinations = 10! / 4! * 6!
combinations = 10 * 9 * 8 * 7 * 6! / 4! * 6!
combinations = 10 * 9 * 8 * 7 / 4 * 3 * 2
combinations = 10 * 3 * 7
combinations = 210
Source:
http://www.1728.org/combinat.htm
Answer:
if you really need help i would guess this is hard 4 me as well my best guess was b
Step-by-step explanation:
Answer:
(2,0)
Step-by-step explanation:
(6-(10-6), 4- (8-4))
Answer:
Notebooks cost $2.75 and pens cost $1.10.
He can also buy 3 notebooks.
Step-by-step explanation:
In order to find this, we need to create two equations given each of the situations.
3n + 2p = 10.45
4n + 6p = 17.60
Now to solve for n, multiply the top equation by -3 and add together.
-9n - 6p = -31.35
4n + 6p = 17.60
----------------------
-5n = -13.75
n = 2.75
Now that we have the value of notebooks, we can find the amount for pens using either equation.
3n + 2p = 10.45
3(2.75) + 2p = 10.45
8.25 + 2p = 10.45
2p = 2.20
p = 1.10
Finally, to find the number of notebooks that he can purchase, find the cost of a notebook with 3 pens.
n + 3p
2.75 + 3(1.10)
2.75 + 3.30
6.05
Now divide 22 by that number
22/6.05 = 3.63
Since we can't have fractional notebooks, we round down to 3.
