If 15 students in a class average 80% on an English exam and 10 students average 90% on the same ...
If 15 students in a class average 80% on an English exam and 10 students average 90% on the same exam, what is the average in percent for all 25 students?
Answer/Solution
84%
Steps/Work
The average percentage = (15 x 80% + 10 x 90%)/25
= (15 x 80% + 10x 80% + 10x10%) / 25 ......(as 90% = 10% + 80% )
=(25x80% + 10x10%)/25
= 80% + 10x10%/25
= 80% + 4%
= 84%
ANSWER:C
= (15 x 80% + 10x 80% + 10x10%) / 25 ......(as 90% = 10% + 80% )
=(25x80% + 10x10%)/25
= 80% + 10x10%/25
= 80% + 4%
= 84%
ANSWER:C