Saturday

January 31, 2015

January 31, 2015

Posted by **jasmine** on Saturday, September 24, 2011 at 11:34pm.

- maths -
**Steve**, Monday, September 26, 2011 at 10:51amSay there are n scores. If the mean is 64, then the total points is just 64n.

Now, we have one more score, and the mean rises to 65. So, we have n+1 scores with mean 65. And we have added 80 points to the total.

64n+80 = 65(n+1)

64n+80 = 65n+65

n = 15

**Answer this Question**

**Related Questions**

statistics! - 1) Entry to a certain University is determined by a national test...

statistics - -A set of seven scores has a mean of 10. If one of the scores is ...

statistics - 2. Why is it important to know the mean and standard deviation for ...

statistics - the admissions policy at a certain university requires that ...

statistics - the admissions policy at a certain university requires that ...

Statistics - Suppose that two different tests A and B are to be given to a ...

Math - 105 91 82 59 97 72 72 88 81 What is the mode of these scores? A.46 B.72 C...

maths - Suppose scores on an IQ test are normally distributed.If the test has ...

maths - the mean of the scores of student during the first 5 months is 23.8 ( ...

RES/342 - Suppose you devised a training program to raise student scores on a ...