Answer:
Step-by-step explanation:
When we take an average of something, we have to add up all the data on the somethings and then divide by the number of somethings we have. Ed takes 5 tests, and we have scores for them; we also have his current average. What we don't know for sure are 2 of the 5 test scores, but we have enough to determine what they are.
If one test has a score of x, and the other test is 3 points less than that, the score on that last test is x - 3. Putting all of that together into an average problem:
and simplfiying a bit:
. Multiply both sides by 5 to get
256 + 2x = 450; subtract 256 from both sides to get
2x = 194 and divide by 2:
x = 97
The one test score was a 97 and the other one, which was 3 less than that, was a 94.
Answer:
68.
Step-by-step explanation:
The common difference d = -19 - (-22) = 3
So the 31st term =
a31 = -22 + (31-1)3
= -22 + 90
= 90 - 22
= 68.
Answer:
Rational because it isn't a repeating decimal
Step-by-step explanation:
8 thousands is equal to 8000.
15 hundreds is equal to 1500.
15 tens is equal to 150.
18 ones is equal to 18.
So just add them up.
8000 + 1500 = 9500.
9500 + 150 = 9650.
9650 + 18 = 9668.
The number is 9668
-4(2y)+11y=15, -8y+11y=3y=15: y=5
X=2(5)=10
To check your work -4(10)+11(5)=15
15=15