Step-by-step explanation:
the mean value is the sum of all data points divided by the number of data points.
first we have 7 tests and their mean value :
(t1 + t2 + t3 + t4 + t5 + t6 + t7) / 7 = 54
that means
(t1 + t2 + t3 + t4 + t5 + t6 + t7) = 54 × 7 = 378
in order for the mean value to be at least 60% after 8 tests, we need to add a t8, so that
(t1 + t2 + t3 + t4 + t5 + t6 + t7 + t8) = 60 × 8 = 480
because only then we have
(t1 + t2 + t3 + t4 + t5 + t6 + t7 + t8) / 8 = 60
and the student passes.
so,
(t1 + t2 + t3 + t4 + t5 + t6 + t7) + t8 = 480
378 + t8 = 480
t8 = 480 - 378 = 102%
the student would have to achieve 102% on the 8th test.
which would be normally impossible, but maybe the tests involve some bonus points.
Answer:
1. 4x + 6
2. -15x + 11
5. -x + 4
6. -4x + 7
9. 5x - 2
12. x + 16
Step-by-step explanation:
Remove the parenthesis for each one so everything's out in the open. Next, you group like terms. The numbers with variables on one side, and the other numbers on the other side. For example:
x + 3x - 2 + 8
Then, you combine like terms:
4x + 6
That's mostly how you do each one.
Volume of a Cylinder = pi * r^2 * h
V / (pi*r^2) = h
12157 / (pi * 9^2) = h = 47.774
Answer:
x+3x+4=3+3 → x=
Step-by-step explanation:
x+3x+4=3+3
4x+4=6
4x=2
x=
Step 1: Set up the proportion
4/12 = 10/x
Step 2: Cross multiply to get
120 = 4x
Step 3: Divide all by 4 to get
30 = x
Answer: So in total, 10 students would spend $30 on lunch!