Terry has taken 4 of the 5 required tests for her math class. her grades are 83, 78, 64, and 91. terry wants to earn at least a "b" for the course. if 80 is the minimum b grade, what is the minimum score terry must get on her last test to get a b?

84

Step-by-step explanation:

Given, grades for first 4 tests are: 83, 78, 64, 91

Goal: To get an average of 80 points over 5 tests.

Let the score for the 5th test be x

Average score = total score for 5 tests ÷ 5 tests

(substituting the given values above),

80 = (83 + 78 + 64 +91 + x) ÷ 5

80 = (316 + x ) ÷ 5

(80)(5) = (316 + x)

400 = 316 + x

x = 400 - 316

x = 84

d

step-by-step explanation:

hello and welcome!

so, when we see the words "proportional" along with a table, we need to know that we're looking numbers that divide by the same thing.

looking at this table, we simply have to do a trial and error, and divide to see which numbers have the same quotient. if you look at choice a & c, they both have equal quotients for three of the numbers, with one exception, so those can't be the answer. looking at b, there is no similarity, so that can't be it. then, we see d; if you divide all the numbers in the table, you'll see that they all divide by two, which is a proportional relationship, and our answer!

also, always remember that the x will always be the number that goes into y, and somewhere behind this table, is a formula. for this specific table, the formula would be:

since our x-value is being divided by two to get the y-value. and if they were to ask for more numbers in the series, this is the formula you would use to find them.

d i think

step-by-step explanation: