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3 years ago

On a standardized exam, the scores are normally distributed with a mean of 135 and a

Mathematics

1 answer:

labwork [276]3 years ago

3 0

Answer:

-1

Step-by-step explanation:

mean, mu = 135.

Standard deviation = 20

X = 115

use the z score formula : $z = \frac{x-mu}{standard deviation}$

to get (115-135)/20 = -1

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Is a number decreased by three squared nonlinear or linear

Dennis_Churaev [7]

Answer:

A number decreased by three squad is a nonlinear.

Step-by-step explanation:

6 0

4 years ago

What is the solution to the equation P over 9= 72?

Fed [463]

P / 9 = 72

Multiply both sidess by 9

P / 9 (9) = 72 (9)

p = 648

4 0

3 years ago

Identify the quotient in the form a + bi. HELP ASAP PLEASE!!

Step2247 [10]

Solving the expression $\frac{4-5i}{2+3i}$ we get $-\frac{7}{13}-\frac{22i}{13}$

So, Option A is correct.

Step-by-step explanation:

We need to solve the expression: $\frac{4-5i}{2+3i}$

Multiplying and dividing by 2-3i

$=\frac{4-5i}{2+3i}*\frac{2-3i}{2-3i}\\=\frac{4-5i*2-3i}{2+3i*2-3i}\\=\frac{4(2-3i)-5i(2-3i)}{(2)^2-(3i)^2}\\=\frac{8-12i-10i+15i^2)}{4-9i^2}\\We\,\,know\,\, i^2=-1\\=\frac{8-12i-10i+15(-1)}{4-9(-1)}\\=\frac{8-15-12i-10i}{4+9}\\=\frac{-7-22i}{13}\\=-\frac{7}{13}-\frac{22i}{13}$

So, solving the expression $\frac{4-5i}{2+3i}$ we get $-\frac{7}{13}-\frac{22i}{13}$

So, Option A is correct.

Keywords: Complex numbers

Learn more about Complex numbers at:

#learnwithBrainly

8 0

3 years ago

Carl earns $5.25 per hour walking his neighbors dogs. He walks them 2/6 of an hour in the morning and 1/2 of an hour in the afte

DIA [1.3K]

2/6 = 1/3 = 20 minutes
1/2 = 30 minutes
20 + 30 = 50 minutes

50 minutes x 7 = 350 minutes = 5 hours and 50 minutes
5 x $5.25 = $26.25
50 minutes = 5/6
5/6 of $5.25 = 4.375

Add $26.25 to the total for 50 minutes to get your answer. :)

7 0

3 years ago

What’s the volume of a cylinder with a radius of 1 and height of 3ft?

Dafna1 [17]

Answer:

9.42

Step-by-step explanation:

V=pir2h

(pi, radius squared, height)

hope this helped!

6 0

3 years ago