Question

Yasmin has earned the following grades on her science tests: 97, 84, 88, and 87. What is the minimum

grade she must get on the last test in order to have an average of 90?

Answer 1

94

Explanation:

The best way to do math problems you dont know is to reverse engineer it,

90*5=450 <- Lets find how many points she must have in total to get

that average by multiplying by how many variables we will

have if the new test is added

450-97-84-88-87=94 <- Now take that number and subtract all given variables

Yasmin must get a 94 on the next test to get exactly 90

Answer 2

Explanation:

Average = Sum /total amount

90=(97+84+88+87+x)/5

90*5=356+x

450-356=x

x=94

so she needs at least 94 marks in her last test for average 90