Please help I need to get this done will brainlist

There were 96 iPads at Fun Elementary. A company donated some iPads and the school purchased 300 more iPads. Now there are 865 i

Zanzabum

Answer:

469 iPads were donated.

Step-by-step explanation:

The school purchased 396 iPads in total: 300+96

Now, you subtract how many the school purchased from the total amount of iPads to see how many iPads were donated: 865-396 = 469

5 0

2 years ago

The article "Occurrence and Distribution of Ammonium in Iowa Groundwater" (K. Schilling, Water Environment Research, 2002:177–18

Papessa [141]

Answer: 95% confidence interval for the difference between the proportions would be (1.31, 1.39).

Step-by-step explanation:

Since we have given that

Number of alluvial wells = 349

Number of quaternary wells = 143

Number of alluvial wells that had concentrations above 0.1 = 182

Number of quaternary wells that had concentrations above 0.1 = 112

Average of alluvial wells = 0.27

Standard deviation = 0.4

Average of quaternary wells = 1.62

Standard deviation =1.70

So, 95% confidence interval gives

alpha = 5% level of significance.

$\dfrac{\alpha}{2}=2.5\%\\\\z_{\frac{\alpha}{2}}=1.96$

So, 95% confidence interval becomes,

$(1.62-0.27)\pm 1.96\sqrt{\dfrac{0.4^2}{349}+\dfrac{1.7^2}{143}}\\\\=1.35\pm 1.96\times 0.020\\\\=(1.35-0.040,1.35+0.040)\\\\=(1.31,1.39)$

Hence, 95% confidence interval for the difference between the proportions would be (1.31, 1.39).

6 0

3 years ago

Read the following sentences from "The Third Bank of the River."

slega [8]

D) from childhood to adulthood my father was very honest and ope

4 0

3 years ago

Sanjay and Felipe are putting together a 500-piece puzzle. Sanjay could do the entire puzzle by himself in 6 hours, while it wou

Nata [24]

What is the time it takes Sanjay to complete the puzzle? 6 hours

What is the time it takes Felipe to complete the puzzle? 8 hours

We can use the general formula of rate and time to solve this problem. Generally we have,

Rate * Time = Work/Job

** where Work/Job for this problem is 1 since they are doing 1 work, which is solving a puzzle

Finding rate of Sanjay:

$R(6)=1\\R=\frac{1}{6}$

Finding rate of Felipe:

$R(8)=1\\R=\frac{1}{8}$

Working together, their rate is the sum,

Total Rate = $\frac{1}{6} + \frac{1}{8} = \frac{7}{24}$ .

Using the general formula again, we can find the time it will take to solve the puzzle when both works together.

$(\frac{7}{24})T=1\\ T=\frac{1}{\frac{7}{24}}= \frac{24}{7} = 3.43$ hours

Rounding the answer, we have 3.4 hours.

ANSWER: 3.4 hours

6 0

3 years ago

Read 2 more answers

Help me with this pls

kozerog [31]

Answer:

x=2 y=17

Step-by-step explanation:

53/17 17x3 = 51 53-51 3 + 1/ x + 1/y

8 0

2 years ago

Read 2 more answers