The average of 10 numbers is -5. A new number is added to the list making the average -6. What is the new number?
1 answer:
Answer:
- 16
Step-by-step explanation:
Average is calculated as
average =
Thus for the given 10 numbers we have
= - 5 ( multiply both sides by 10 )
total = - 50
let the number added be x, then
= - 6 ( multiply both sides by 11 )
total + x = - 66, that is
- 50 + x = - 66 ( add 50 to both sides )
x = - 16
The new number is - 16
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Answer:
The answer is below
Step-by-step explanation:
The z score is a score used to determine the number of standard deviations by which the raw score is above or below the mean, it is given by the equation:
Given that μ = 650, σ = 50. To find the probability that 5 students who have a mean of 490, we use:
From the normal distribution table, P(x < 490) = P(Z < -7.16) = 0.0001 = 0.01%
Since only a small percentage of people score about 490, hence the local newspaper editor should write a scathing editorial about favoritism