Question

A student scores 72 out of 100 on a test. If the maximum score on the next test is also 100 points, what score does the student need to maintain at least an average of 80?

Answer 1

let the score be x then (72+x)/2>=80

Answer 2

does it help?

Answer 3

The 2 tests' points add together to make 200.

A percentage is in the form \[\ \frac{x}{100} \], So divide our 200 score by 2 to get it in 100-terms
Call y the score on the 2nd test. We want \[\frac{72+y}{2}\]
to equal at least 80
\[\frac{72+y}{2} >/= 79\]

Answer 4

can you help me through it

Answer 5

Re-arrange and find y

Answer 6

@henpen why 79

Answer 7

not 80

Answer 8

Sorry, 80, the 'or equal to' sign was breaking on me!