Question

At academy Ali's average score in first four full-length papers is 80. Assuming that he can earn no more than 90 on any test. What is the least score he must earn on his 5th test and still have a chance of an overall average of 80 on all the seven test?

Answer 1

Step-by-step explanation:

Let he scores a,b,c,d,e score in his respective papers.

so

$\frac{a + b + c + d}{4} = 80$

$a + b + c + d = 320$

Now

according to question

$\frac{a + b + c + d + e}{5} = 80$

$a + b + c + d + e = 400$

$320 + e = 400 \\ e = 80$

since a + b + c + d=320.

e=80

hopefully you understand!!!!!