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 point
1 answer:
Answer:
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
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Answer:
Value of h greater than 5.4 will make inequality false.
Step-by-step explanation:
This question is incomplete; here is the complete question.
The Jones family has saved a maximum of $750 for their family vacation to the beach. While planning the trip, they determine that the hotel will average $125 a night and tickets for scuba diving are $75. The inequality can be used to determine the number of nights the Jones family could spend at the hotel 750 ≥ 75 + 125h. What value of h does NOT make the inequality true?
From the given question,
Per night expense (expected) = $125
If Jones family stays in the hotel for 'h' days then total expenditure on stay = $125h
Charges for scuba diving = $75
Total charges for stay and scuba diving = $(125h + 75)
Since Jones family has saved $750 for the vacation trip so inequality representing the expenses will be,
125h + 75 ≤ 750
125h ≤ 675
h ≤
h ≤ 5.4
That means number of days for stay should be less than equal to 5.4
and any value of h greater than 5.4 will make the inequality false.
Answer: 1 hour 20 minutes
Step-by-step explanation:
Given : The old machine could shred a truckload of paper in 4 hours.
Rate of work done by old machine =
The new machine could shred the same truckload in 2 hours.
Rate of work done by new machine =
Let 't' be the time taken by both of them working together , then we have the following equation:-
Since 1 hour = 60 minutes
Then,
Hence, it will take 1 hour 20 minutes to shred the same truckload of paper if Ron runs both shredders at the same time.