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3 years ago

Prove: If C⊂A and D⊂B then D−A⊂B−C

1 answer:

3 0

Let $x\in D\setminus A$ , so that $x\in D$ but $x\not\in A$ . Since $D\subset B$ , it follows that $x\in B$ , and since $C\subset A$ , it follows that $x\not\in C$ , which means $x\in B\setminus C$ .

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Y = n(n + 1) please help, thanks!!!

Yuri [45]

Answer:

Y=n^2+n

Step-by-step explanation:

6 0

2 years ago

find rodrigos percent increase or decrease in sales each week. week 1, is 17 wwek 2, is 25 week 3, is 18 and week 4, is 27. his

sveticcg [70]

Answer: The multiplication factor of increase should be inverse of the multiplication factor of decrease.

e.g. Say you have a number 100. You increase it by 25%. The multiplication factor is 5/4 i.e. when you multiply 100 by 5/4, you get 100*5/4 = 125. This is 25% more than 100. Now you want to decrease it by a certain % such that you get 100 back. Basically, 100*5/4 * x = 100 So x = 4/5 (inverse of 5/4) Hence, you decrease by 20% (the multiplication factor of 20% is 4/5) or Use this formula: cumulative % change = a + b + ab/100 You want the cumulative change to be 0. a + b + ab/100 = 0 If you know that you are increasing by 25% and want to find the % by which you should decrease to get the same number, 25 + b + 25b/100 = 0 5b/4 = -25 b = -20 So you need to decrease (hence you get the -ve sign) by 20%.

3 0

3 years ago

Please help me. I need help with this question.

iogann1982 [59]

Answer:

$367.38 is the cost to stain the entire deck.

Step-by-step explanation:

Here is what you need to know beforehand:

Diameter is a line that goes through a circle. Radius is a line that goes from the edge of the circle all the way to the center/a line that goes halfway through the circle.

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First, find the area of the circle. Here is the formula:

Area = 3.14 (Pi) x r²

Since radius is half of the diameter (as explained above), you'll need to divide the diameter in half: 12m/2 = 6m

So the formula will look like this:

Area = 3.14 x 6²

Then, you just do the math:

Area = 3.14 x 6²

Area = 3.14 x 36

Area = 113.04

The goal of the problem is to find the amount of money Emma needs. Finally, all you need to do is multiply the amount it cost to stain per square meter by the total area of the deck:

Answer = 113.04 x 3.25

Answer = 367.38

$367.38 is the cost to stain the entire deck.

4 0

3 years ago

Natalie invested $1,200 in an account paying an interest rate of 6.4% compounded continuously. Assuming no deposits or withdrawa

Keith_Richards [23]

Answer:

FV=$3,445

Step-by-step explanation:

FV=PV(1+i)^n (FV: Future value, PV: Present value)

i=0.064

n=17

FV=1200(1+0.064)^17

FV=3444.9975

FV=$3445.00

8 0

3 years ago

Will the answer to this expression be POSITIVE or NEGATIVE? - 100 - (- 98)

mina [271]

Answer:

-100-(-98)=-100+98=-2 then negative

3 0

2 years ago

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