Question

Students took an exam. Here are their grades. What is the class' mean grade? What

is the median grade?
(Round the average to the nearest whole number.)
65, 70, 70, 80, 80, 85, 85, 85, 90, 90, 100

Answer 1

See below ↓↓

Explanation:

Mean

• Sum of grades / No. of grades
• 65 + 70 + 70 + 80 + 80 + 85 + 85 + 85 + 90 + 90 + 100 / 10
• 150 + 140 + 170 + 170 + 190 + 80 / 10
• 500 + 320 + 80/ 11
• 900/11
• 81.81

Median

• The middle number is the median as the set has an odd number of data
• ⇒ 85

Answer 2

mean=81.81

median=85

Explanation:

MEAN.

`(65 + 70 + 70 + 80 + 80 + 85 + 85 + 85 + 90 + 90 + 100)/(11)`

`= 81.81`

MEDIAN

Since it's already arranged in ascending order, the middle number is taken as the median

which is 85.

i hope this helps