A combination is an unordered arrangement of r distinct objects in a set of n objects. To find the number of permutations, we use the following equation:
n!/((n-r)!r!)
In this case, there could be 0, 1, 2, 3, 4, or all 5 cards discarded. There is only one possible combination each for 0 or 5 cards being discarded (either none of them or all of them). We will be the above equation to find the number of combination s for 1, 2, 3, and 4 discarded cards.
5!/((5-1)!1!) = 5!/(4!*1!) = (5*4*3*2*1)/(4*3*2*1*1) = 5
5!/((5-2)!2!) = 5!/(3!2!) = (5*4*3*2*1)/(3*2*1*2*1) = 10
5!/((5-3)!3!) = 5!/(2!3!) = (5*4*3*2*1)/(2*1*3*2*1) = 10
5!/((5-4)!4!) = 5!/(1!4!) = (5*4*3*2*1)/(1*4*3*2*1) = 5
Notice that discarding 1 or discarding 4 have the same number of combinations, as do discarding 2 or 3. This is being they are inverses of each other. That is, if we discard 2 cards there will be 3 left, or if we discard 3 there will be 2 left.
Now we add together the combinations
1 + 5 + 10 + 10 + 5 + 1 = 32 choices combinations to discard.
The answer is 32.
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Note: There is also an equation for permutations which is:
n!/(n-r)!
Notice it is very similar to combinations. The only difference is that a permutation is an ORDERED arrangement while a combination is UNORDERED.
We used combinations rather than permutations because the order of the cards does not matter in this case. For example, we could discard the ace of spades followed by the jack of diamonds, or we could discard the jack or diamonds followed by the ace of spades. These two instances are the same combination of cards but a different permutation. We do not care about the order.
I hope this helps! If you have any questions, let me know :)
Answer:
D is the answer
Step-by-step explanation:
We want a mixture of low-fat and whole milk to equal 32ounces
Therefore, we know one equation is:
l + w = 32
That 32 ounce mixture should be 2% butter fat
So the amount of butter fat we want is
2% of 32 = 0.64 ounces
At the same time, this mixture contains low-fat and whole milk, which contain 1% and 3.25% butter fat respectively.
therefore, the butter fat in low-fat and whole milk is 0.01l and 0.0325w respectively.
The coefficients are just the percentages in decimal form
Due to the law of conservation of mass,
The addition of these two should yield the final amount of butter fat, meaning the other equation is:
0.01l + 0.0325w = 0.64
Answer:
|-1/4 - 3/4|
Step-by-step explanation:
To get the distance, take the absolute value of the second point minus the first point
| 3/4 - - 1/4|
|3/4 + 1/4|
We can also take the absolute value of the first point minus the second point
|-1/4 - 3/4|
To solve for the total amount that Alice paid for the 3 yards cloth, multiply the cost per yard with the additional 5% to number of yards. 5% of 93 is 4.65. The total cost per yard of cloth is 97.65. Multiplying the total cost with 3 will give 292.95. Thus, Alice paid 292.95 dollars in total.
