The question is in the picture PLEASE HELP ME!!! idk how to do this
1 answer:
Answer:
35
Step-by-step explanation:
Put the numbers in the formula and do the arithmetic.
nCk = n!/(k!(n -k)!)
7C3 = 7!/(3!(7-3)!) = 7·6·5/(3·2·1) = 7·5 = 35
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It is convenient to use the largest of the factorials in the denominator to cancel as many factors as you can from the numerator, then cancel factors from the remaining numbers. Here after canceling 4! = 4·3·2·1 from the numerator, we are left with 7·6·5 divided by 3! = 3·2·1 = 6. Obviously, this will cancel the 6 in the numerator product, leaving only 7·5 = 35.
Some graphing and/or scientific calculators will have this function built in.
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He pays $135 for 3 years. So that’s $45/year. Considering 900 is your 100%, how many percents are represented by $45 in 900?
1)
You can see that 900 = 9x100.
So you can divide 900 by 9 to get 100.
That means you can also divide 45 by 9 (it’s proportional)
You have 45 for 900, you divide by 9 so you get 5 for 100 -> 5%
Or 2)
(Photo)
It’s a cross-multiplication :
(45 x 100)/900 = 5%
So the interest rate is 5%.
(Sorry if it’s confusing, English isn’t my first language..)
1)
You can see that 900 = 9x100.
So you can divide 900 by 9 to get 100.
That means you can also divide 45 by 9 (it’s proportional)
You have 45 for 900, you divide by 9 so you get 5 for 100 -> 5%
Or 2)
(Photo)
It’s a cross-multiplication :
(45 x 100)/900 = 5%
So the interest rate is 5%.
(Sorry if it’s confusing, English isn’t my first language..)