Answer:
Step-by-step explanation:

(We know this from a=1/9 and r=3)
Simplifying this, we get:

Since we're finding the first term that exceeds 1000, let's set it equal to 1000.

Multiplying both sides by 27


n≈9.2
We have to round n up, since if n=9, the value would be <1000.
Therefore n=10. Substituting n=10,

=2187
Therefore the first term that exceeds 1000 is 2187, and it is the 10th term
Answer: A; 6.3%
Step-by-step explanation:
Problem 1
For the first problem, we first want to find y so that we can plug it into the expression.
We can use elimination method for the system of equations to solve.
3x+3y=21
3x-y=5
We subtract both equations to eliminate x.
4y=16 [divide both sides by 4]
y=4
Now that we know y, we can plug it into the expression.
[divide]
[subtract]

We know that the answer is A.
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Problem 2
For the second problem, we need to know how to calculate percent error. The formula for precent error is
. We know that the exact value is 80 because the buyer was supposed to given 80. 75 is the measured value because that was what the buyer was given.
[subtract]
[solve absolue value]
[divide]
[multiply]

Since the problem said to round to one decimal place, we know that the answer is 6.3%.
Answer:
27/5 or 5 2/5
Step-by-step explanation:
Assuming you mean 9 x 3/5
The answer would be
27/5
in Decimals, it would be
5.4
and in mixed numbers form it would be
5 2/5