Share 120 in the ratio 1:5

A total of 50 juniors and seniors were given a mathematics test. The 35 juniors attained an average score of 80 while the 15 sen

Alik [6]

Answer:

77

Step-by-step explanation:

Firstly, we need to calculate the total score of the junior students and the total score of the senior students.

The total score of the junior students is 35 * 80 = 2,800

The total score of the senior students is 15 * 70 = 1050

The total score is thus 2,800 + 1,050 = 3,850

The average score of the 50 students is thus 3,850/50 which equals 77

8 0

3 years ago

What are the values of x and y if this equation is true?<br><br> 22(x + yi) + (28 + 4i) 72 – 62i

ASHA 777 [7]

Answer:

x = 2

y = -3

Step-by-step explanation:

The given equation is,

22(x + yi) + (28 + 4i) = 72 - 62i

By solving this equation further,

22x + 22yi + 28 + 4i = 72 - 62i

(22x + 28) + (22y + 4)i = 72 - 62i

Now both the sides of the equation is in the form of complex number,

By comparing real and imaginary parts given on both the sides,

22x + 28 = 72

22x = 72 - 28

22x = 44

x = 2

22y + 4 = -62

22y = -62 - 4

22y = -66

y = -3

Therefore, x = 2 and y = -3 are the values for which the given equation is true.

8 0

3 years ago

Every day, Luann walks to the bus stop and the amount of time she will have to wait for the bus is between 0 and 12 minutes, wit

Nana76 [90]

Answer:

a. 341.902.

Step-by-step explanation:

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the z-score 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 p-value, we get the probability that the value of the measure is greater than X.

n instances of a normal variable:

For n instances of a normal variable, the mean is $n\mu$ and the standard deviation is $s = \sigma\sqrt{n}$

60 days, for each day, mean 6, variance of 12.

So

$\mu = 60*6 = 360$

$s = \sqrt{12}\sqrt{60} = 26.8328$

What is the 25th percentile of her total wait time over the course of 60 days?

X when Z has a p-value of 0.25, so X when Z = -0.675.

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

$-0.675 = \frac{X - 360}{26.8328}$

$X - 360 = -0.675*26.8328$

$X = 341.902$

Thus, the correct answer is given by option A.

3 0

2 years ago

Simplify each expression involving signed numbers.

7nadin3 [17]

Answer:

-7 - 2 = -9 (combine the numbers,simplify)

12 + (-4) = 8 (Simplify the Expression)

-8(-6) = 48 (Simplify the Expression)

18/-3 = -6 ( Simplify the Expression)

Hope this helps :)

3 0

2 years ago

Read 2 more answers

if f(x)=3/x+2-sqrtx-3 complete the following statement. The domain for f(x) is all real numbers___ than or equal to 3

Stolb23 [73]

The domain of the function is the set of all the values of x that would allow the function to have real values. Since the radicand is x - 3, the value of x cannot be less than 3 because that would make the value of sqrt (x - 3) an imaginary number. Thus, the domain should be all numbers GREATER than or equal to 3.

6 0

3 years ago