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2 years ago

Easy math for smart people problem: 5(2d+4)=35

Mathematics

1 answer:

Likurg_2 [28]2 years ago

6 0

Answer:

3/2 (decimals): 1.5

Step-by-step explanation:

1. 5(2d+4)=35 -> multiply 5 to (2d+4)

2. 10d + 20 = 35

3. Subtract 20 by both sides

10d = 35-20

10d = 15

4. divide 10 by both sides

d = 15/10

d = 3/2

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Kinsley took out a loan for $2000 with interest rate of 4.8% to pay off the loan in two years she has to make payments of $100 e

atroni [7]

Answer:

it is in answer

Step-by-step explanation:

6 0

3 years ago

Consider a sequence whose first three

snow_tiger [21]

Answer:

Below, depends if 27 is term number 1 or term number 0. Answered for both cases.

Step-by-step explanation:

The most common sequences are arithmetic and geometric, so lets check those first.

Arithmetic first since its the easiest.

to go from 27 to 21 we subtract 6, if we subtract 6 from 21 again we get to 15, which is what we need, so it is indeed arithmetic.

Explicit formula is basically of the form of y=mx+b with an arithmetic sequence. the m is the common difference and b is the first term minus the common difference. so lets fill those in. y = -6x + 33

Then it usually has n as the x and y f(n) so we'll just put those in

f(n) = -6n + 33

This si as long as the first term is labeled as term number 1 and not term number 0. if you have 27 as term 0 instead just make 33 back to 27, so f(n) = -6n + 27

Let me know if this doesn't make sense.

5 0

3 years ago

The sales of a grocery store had an average of $8,000 per day. The store introduced several advertising campaigns in order to in

oksano4ka [1.4K]

Answer:

Null hypothesis: $\mu \leq 8000$

Alternative hypothesis: $\mu > 8000$

$z=\frac{8300-8000}{\frac{1200}{\sqrt{64}}}=2$

$p_v =P(Z>2)=0.0228$

Step-by-step explanation:

1) Data given and notation

$\bar X=8300$ represent the sample mean

$\sigma=1200$ represent the population standard deviation

$n=64$ sample size

$\mu_o =800$ represent the value that we want to test

$\alpha$ represent the significance level for the hypothesis test.

z would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

2) State the null and alternative hypotheses.

We need to conduct a hypothesis in order to check if the mean is higher than 8000, the system of hypothesis are :

Null hypothesis: $\mu \leq 8000$

Alternative hypothesis: $\mu > 8000$

Since we know the population deviation, is better apply a z test to compare the actual mean to the reference value, and the statistic is given by:

$z=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}}$ (1)

z-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

3) Calculate the statistic

We can replace in formula (1) the info given like this:

$z=\frac{8300-8000}{\frac{1200}{\sqrt{64}}}=2$

4) P-value

Since is a one-side upper test the p value would given by:

$p_v =P(Z>2)=0.0228$

5) Conclusion

If we compare the p value and the significance level assumed, for example $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, so we can conclude that the mean is significantly higher than $8000.