Mrs. Gifford's class consists of 15 girls and 25 boys.On the first test the mean of the girls’ scores was 80 and the mean of the boy’s scores was 70. What was the class mean? (Remember the class mean is not just averaging the two means)On the second test, the class mean was 80 and the mean girl’s scores was 75. What was the mean of the boy’s scores?
I ONLY NEED THE SECOND TEST MEAN!!!!!
IDK but can u help on my questions?
"the class mean was 80" ---> so the total of all the scores
= 80*40 = 3200
"the mean girl’s scores was 75" ----> the total of all the girls' scores
= 15*75 = 1125
which leaves 2075 for the total of the boys' scores.
But there were 25 boys, so the boys' mean = 2075/25 = 83
thanx :)
To find the mean of the boy's scores on the second test, we need to use the information given about the class mean and the mean girl's scores.
Let's break down the information we have:
- In Mrs. Gifford's class, there are 15 girls and 25 boys.
- On the first test, the mean of the girls' scores was 80 and the mean of the boys' scores was 70.
- On the second test, the class mean was 80 and the mean girl's score was 75.
To find the mean boy's score on the second test, we can start by finding the total scores for both girls and boys on the second test.
Total girls' score on the second test = Mean girl's score x Number of girls
Total girls' score on the second test = 75 x 15
Next, let's subtract the total girls' score on the second test from the total class score on the second test to find the total boys' score on the second test.
Total boys' score on the second test = Total class score on the second test - Total girls' score on the second test
Since the class mean is equal to the sum of all the individual scores divided by the number of students, we can determine the total class score on the second test.
Total class score on the second test = Class mean x Total number of students
Total class score on the second test = 80 x (15 + 25)
Finally, we can substitute the values we have calculated into the equation to find the mean boys' score on the second test.
Mean boys' score on the second test = (Total boys' score on the second test) / Number of boys
Mean boys' score on the second test = (Total class score on the second test - Total girls' score on the second test) / 25
By following these steps and calculations, you can find the mean of the boys' scores on the second test.