Answer:
She did not separate her friends into different groups, and she didn't apply a treatment.
Step-by-step explanation:
Alice decides to ask 25 of her friends if they listen to music while they do their homework and what their grades are.
She finds that her friends who have high grades also listen to music while they do their homework.
She tells her parents that she has proven that listening to music while doing homework will cause her grades to improve.
First of all it cannot be proven like this way.
Secondly, she did not use a random sample, and did not separated her friends into groups and applied treatment.
So, the answer is She did not separate her friends into different groups, and she didn't apply a treatment.
Answer:
70 cards
Step-by-step explanation:
Let A = the number of Andys cards
J = the number of Jons cards
Jon and Andy had a total of 560 trading cards
A+J = 560
After Jon gave 1/9 of his trading cards to Andy, they has an equal number of trading cards
J - 1/9 J = 1/9 J +A
Combine like terms
8/9 J = 1/9 J +A
Subtract 1/9J from each side
7/9J = A
Substitute this into A +J = 560
7/9J +J = 560
Combine like terms
7/9J +9/9J = 560
16/9 J = 560
Multiply each side by 9/16
9/16 *16/9 J = 560 *9/16
J =315
Jon originally had 315 cards
Now we need to find Andys cards
7/9J = A
7/9 (315) =A
245=A
How many more trading cards did Jon have that Andy in the beginning?
We need to take Jons cards and subtract Andys cards
J-A
315-245
70


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Equation of line in point - slope form :

Here :


Answer:
O -1+ 3/
Step-by-step explanation:
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