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2 years ago

Denise has taken four math tests this semester and

Mathematics

1 answer:

Viefleur [7K]2 years ago

4 0

Answer:

Step-by-step explanation:

Setup an equation. Add the 5 tests together, the unknown test will be represented by x, Since there are 5 tests total, you will divide by 5. to find the average.

$\frac{89 + 85+96+87+x}{5} = 90$

To solve first multiply both side by 5.

$(5) \frac{89 + 85+96+87+x}{5} = 90 (5)$

$89 + 85+96+87+x = 450$

Add the left side and then solve for x

$357 + x = 450$

Subtract 357 from both sides

357 - 357 + x = 450 - 357

x = 93

The last test has to be a score of 93 to get an average of 90.

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Which function represents exponential decay

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The formula for exponential growth and decay is: In this function, a symbolizes the origin value, such as the starting population or the beginning dosage level. The variable b represents the growth or decay factor. If b > 1, the function signifies exponential growth.

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3 years ago

3.7 times .26 equal=

Sveta_85 [38]

Answer:

.96

Step-by-step explanation:

7 0

3 years ago

Read 2 more answers

According to the National Vital Statistics, full-term babies' birth weights are Normally distributed with a mean of 7.5 pounds a

Sav [38]

Answer:

68.26% probability that a randomly selected full-term pregnancy baby's birth weight is between 6.4 and 8.6 pounds

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this problem, we have that:

$\mu = 7.5, \sigma = 1.1$

What is the probability that a randomly selected full-term pregnancy baby's birth weight is between 6.4 and 8.6 pounds

This is the pvalue of Z when X = 8.6 subtracted by the pvalue of Z when X = 6.4. So

X = 8.6

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{8.6 - 7.5}{1.1}$

$Z = 1$

$Z = 1$ has a pvalue of 0.8413

X = 6.4

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{6.4 - 7.5}{1.1}$

$Z = -1$

$Z = -1$ has a pvalue of 0.1587

0.8413 - 0.1587 = 0.6826

68.26% probability that a randomly selected full-term pregnancy baby's birth weight is between 6.4 and 8.6 pounds

6 0

3 years ago

Help!

AnnyKZ [126]

Answer:

2 stars and 3 points

Step-by-step explanation:

8+2=10

10+4=14

14+6=20

the value increases by 2 each time.

12+3=15

15+6=21

21+9=30

this value is based on multiples of three.

Good luck

7 0

3 years ago

Read 2 more answers

The ratio of cars to trucks is 9:4. The ratio of trucks to SUV's is 12:21. There are 54 cars.

Elenna [48]

Answer:

Number of trucks = 24

Number of SUVs = 24

Step-by-step explanation:

The ratio of cars to trucks is 9:4

The total ratio of cars to trucks is

9+4 = 13

Let x = sum of cars and trucks.

There are 54 cars. Therefore,

x = 54 + t trucks

Number of cars = ratio of cars/ total ratio × sum of cars and trucks. This means,

54 = 9/13 × x

9x / 13 = 54

9x = 13 × 54

9x = 702

x = 702 / 9 = 78

x = 54 + t trucks = number of trucks = 78 = 54 + t trucks

t trucks = 78 - 54 = 24

Number of trucks = 24

The ratio of trucks to SUVs is 12:21

The total ratio of cars to trucks is

12 + 21 = 33

Let y = sum of trucks and SUVs

There are 24 trucks. Therefore,

x = 24 + s SUVs

Number of trucks = ratio of trucks / total ratio × sum of trucks and SUVs. This means,

24 = 12 / 33 × y

12y / 33 = 24

12y = 24 × 33

12y = 792

y = 792 / 12 = 66

y = 24 + s SUVs

66 = 24 + s SUVs

s SUVs = 66 - 24 = 42

Number of SUVs = 24

7 0

3 years ago