SOLUTION: If Madeline scores 97% on her next math test, her average will be 90%. If she scores 73%, her average will be 87%. How many tests has Madeline already taken? a) 6 b) 7 c) 8 d) 9 e

Question 251677: If Madeline scores 97% on her next math test, her average will be 90%. If she scores 73%, her average will be 87%. How many tests has Madeline already taken?
a) 6 b) 7 c) 8 d) 9 e) none of these
Answer by richwmiller(17219) (Show Source): You can put this solution on YOUR website!

let n= tests already taken
a=previous average
(97+n*a)/(n+1)=90
(73+n*a)/(n+1)=87
b)7
previous average was 89
check
(97+(7*89))/8=90
(97+623)/8
720/8=90
90=90
(73+(7*89))/8=87
(73+623)/8=87
696/8=87
87=87
RELATED QUESTIONS
If Beth gets a 97 on her next math test, her average will be 90. If she gets 73, her... (answered by hitokiri15,palanisamy)

Before she took her last exam, the average of Tara�s exam scores was 89. She figures... (answered by solver91311,Edwin McCravy)

in an English class, each student's final grade is the average of the scores on n tests.... (answered by Fombitz)

If Brittany gets a 97 on her next math test, her average will be 89. However, if she gets (answered by jim_thompson5910)

If Brittany gets a 97 on her next math test, her average will be 89. However if she gets... (answered by Alan3354)

If Joe gets 97 on his next math test, his average will be 90. If he gets 73, his average... (answered by JBarnum)

If Joe gets 97 on his next math quiz, his average will be 90. If he gets 73, his average (answered by Boreal)

Mary took 5 English tests. Her scores were 78%, 89%, 98%, 67%, and 90%. What must she... (answered by nerdybill)

Peter and Diane have the same average in mathematics. On the next test, Diane scored 97%... (answered by ankor@dixie-net.com)