Current Price = $70
Percentage increase = 100% of $70 = $70
Sale Price = $70 + $70 = $140
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Answer: The sale price of the cell phone is $140.
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Answer:
a = 20
Step-by-step explanation:
7a + 2a + a − 9a = 20
Combine like terms
10a -9a = 20
a =20
Not an expertise on infinite sums but the most straightforward explanation is that infinity isn't a number.
Let's see if there are anything we missed:
∞
Σ 2^n=1+2+4+8+16+...
n=0
We multiply (2-1) on both sides:
∞
(2-1) Σ 2^n=(2-1)1+2+4+8+16+...
n=0
And we expand;
∞
Σ 2^n=(2+4+8+16+32+...)-(1+2+4+8+16+...)
n=0
But now, imagine that the expression 1+2+4+8+16+... have the last term of 2^n, where n is infinity, then the expression of 2+4+8+16+32+... must have the last term of 2(2^n), then if we cancel out the term, we are still missing one more term to write:
∞
Σ 2^n=-1+2(2^n)
n=0
If n is infinity, then 2^n must also be infinity. So technically, this goes back to infinity.
Although we set a finite term for both expressions, the further we list the terms, they will sooner or later approach infinity.
Yep, this shows how weird the infinity sign is.
Answer:
None of them are irrational.
Step-by-step explanation:
An Irrational Number is a real number that cannot be written as a simple fraction.
Therefore:
-4 can be written as -4/1
2/9 is already in fraction
8.26 can be written as 826/100
11 can be written as 11/1
None of them are irrational.
However numbers like 
are irrational as they can not be represented as fractions.
