Question

5) Out of 30 students the 13 boys had a mean average score of 65% in their last science test. All 30 students in the class had a mean average score of 72%. Find the mean average of the girls. Give your answer to 2dp.

Answer 1

Answer:

77.35%

Step-by-step explanation:

Find the total number of girls:

Total number of students = 30

Total number of boys = 13

Total number of girls = 30 - 13 = 17

Find the total score of the class:

Average = 72%

Total = 72 x 30 = 2160%

Find the total score of the boys:

Average = 65%

Total = 65 x 13 = 845%

Find the total score of the girls:

Total = 2160 - 845 = 1315%

Find the average score of the girls:

Number of girls = 17

Total score = 1315%

Average = 1315 ÷ 17 = 77.35%

Answer: 77.35%