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3 years ago

18

Mathematics

1 answer:

Cloud [144]3 years ago

3 0

Answer: 100

Step-by-step explanation:

a) The mean of a normal distribution is also the median. Half the population will have values above the mean. Half of 200 is 100, so ...

... 100 students will have grades above 70%.

b) 84% is 14% above the mean. Each 7% is 1 standard deviation, so 14% is 2 standard deviations above the mean. The empirical rule tells you 95% of the population is within 2 standard deviations of the mean, so about 5% of students (10 students) got grades higher than 84% or lower than 56%. The normal distribution is symmetrical, so we expect about 5 students in each range.

... about 5 students will have grades above 84%.

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Write a relationship for a function whose k(x) values are 5 more than four times the principal square root of x .

bearhunter [10]

Answer:

$k(x)=5+4\sqrt{x}$

Step-by-step explanation:

Write a function whose k(x) values are 5 more than four times the principal square root of x.

So,

the principal square root of x $=\sqrt{x};$

four times the principal square root of x $=4\sqrt{x};$

5 more than four times the principal square root of x $=5+4\sqrt{x};$

Thus,

$k(x)=5+4\sqrt{x}$

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Answer:

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Step-by-step explanation:

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At the beginning of the month, the value of a stock is $78.35. By the end of the month the value of the stock has changed by a l

liberstina [14]

Answer:

Step-by-step explanation:

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At the end, the loss = $12.80

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3 years ago

A rectangular gasoline tank can hold 45.0 kg of gasoline when full. what is the depth of the tank if it is 0.450 m wide by 0.900

garri49 [273]

The answer is 0.154 m

Step 1. Calculate the volume of gasoline tank (V) using the known mass (m) and density of gasoline (D).
D = m/V
⇒ V = m/D
D = 719.7 kg/m³
m = 45.0 kg
V = 45.0 kg/719.7 kg/m³ = 0.0625 m³

Step 2. Calculate the depth of the tank (d) using the known volume (V) of gasoline and width (w) and length (l) of the tank:
V = d * w * l
0.0625 = d * 0.900 * 0.450
0.0625 = d * 0.405
d = 0.0625 / 0.405
d = 0.154 m

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3 years ago