A set of N = 20 exam scores has a mean of m = 50. The instructor discovered that an error was made grading one exam, so 20 points are added to that student's score. After adding the 20 points, what is the new mean for the class? Hint: Write down the formula for the mean and fill in all known information. What is the new mean for the class?

The new mean for the exam scores is 51

Step-by-step explanation:

the mean can be calculated using the formula

mean of scores =

before the 20 points was added, the mean of the score was = 50.

Inserting this into the formula, we have:

50 =

from this, we can compute the sum total of the scores as

sum total = 50 × 20 = 1000

when the extra 20 marks is added, the sum of the entire scores will be changed to 1000 + 20 = 1020.

Hence the new mean will be computed as (New Sum total of scores / Number of students)

= = 51.

∴ The new mean of the scores is = 51

2 & 7

step-by-step explanation:

he climbs 300 ft/hr at a constant rate. the peak is at 1,500 ft.

when going up, he reaches 600 ft in 2 hours. remember, that he is going in a constant rate. divide 600 with 300:

600/300 = 2

assuming that he takes the same route back (meaning that it's a 1500 ft route back, you can solve.

note also that you are solving when he gets back to 600 ft after he reaches the peak.

first, find the amount of hours it takes to get up the peak. divide the total amount (1500), with the ft/her (300) to get the amount of hours (x):

1500/300 = x

x = 5

it takes jamie 5 hours to get up. now, he is returning down, and reaches 600 (his current destination). remember that he climbs at a constant 300 ft/hr. divide 600 with 300:

600/300 = x

x = 2

now add the two numbers together.

x = 5 + 2 = 7

jamie takes 7 hours to go up the mountain and reach his current position when descending.

(total amount/constant rate) = (time).

remember that it is a constant rate, so in total, when he gets back down the mountain, it will take the same amount of time as when he goes up. the total amount for the round trip is: 5 + 5 = 10.

~

idk wbu

step-by-step explanation: