what is the minimum grade needed on test 6 to maintain a 70 test average?

Question

here are the grades 95,86,80,76,83 what do i need to make on test 6 to maintain a 70 average? could you please show me how you got the answer? thanks a bunch!!

Answer 1

Let x be your last test grade.

(95 + 86 + 80 + 76 + 83 + x)/6 = 70
(420 + x)/6 = 70
420 + x = 420
x = 0

You can skip the last test and still get a 70 average.

Answer 2

Let your grade on the 6th test be S. Then, you want your average to be 70. So you need to have (95+86+80+76+83+S)/6=70. We get:
(420+S)/6=70 which then gives us 420 + S = 6*70 and then we get S = 420- 420 = 0. Thus, you can get 70 without even showing up to the test. I say you go there and do all you can. You can't do worse than 0 and you'll probably get some points at least. If you then want to find your average after you get the grade on the 6th test, then substitute it for S in the above formula and solve it!
Good luck!

Answer 3

You can get a 0 on the test 6 and still average a 70.

95+86+80+76+83 = 420, 420 / 6 = 0

Answer 4

(95+86+80+76+83+x)/6 = 70
Multiply both sides by 6:
(95+86+80+76+83+x) = 420
420 + x = 420
Subtract 420 from both sides:
x = 0

You don't even need to take the test, but if you want higher than a 70 test average, take it.

Answer 5

Hello
The average of 6 number is their sum divided by 6. So let x = the sixth number and we have (420 + x )/6 >= 70 so 420 + x >= 420 so x >= 0.

Hope This Helps!!

Answer 6

95(1/6) + 86(1/6) + 80(1/6) + 76(1/6) + 83(1/6) +x(1/6) = 70

and the answer is....

0, you could make a zero, and still have a seventy average