Answer:
c
Step-by-step explanation:
Answer:
Negative Correlation
Step-by-step explanation:
We see that the overall trend is going from up to down. If you were to draw a best line of fit, it would have a negative slope. Therefore, our correlation is negative.
Answer:

Step-by-step explanation:
If t is the number of days since Sofia took the medication of 10 mg, then the amount of medication in her system after t days will be
.
So, the concentration of medicine in blood decreases by a factor of one half every day.
If we count the number of days from today and Lexi takes 10 mg of the same medicine four days later then the amount of medicine left on her body after t days will be
. (Answer)
Answer:
It's 15/7
Step-by-step explanation:
First of all, the modular inverse of n modulo k can only exist if GCD(n, k) = 1.
We have
130 = 2 • 5 • 13
231 = 3 • 7 • 11
so n must be free of 2, 3, 5, 7, 11, and 13, which are the first six primes. It follows that n = 17 must the least integer that satisfies the conditions.
To verify the claim, we try to solve the system of congruences

Use the Euclidean algorithm to express 1 as a linear combination of 130 and 17:
130 = 7 • 17 + 11
17 = 1 • 11 + 6
11 = 1 • 6 + 5
6 = 1 • 5 + 1
⇒ 1 = 23 • 17 - 3 • 130
Then
23 • 17 - 3 • 130 ≡ 23 • 17 ≡ 1 (mod 130)
so that x = 23.
Repeat for 231 and 17:
231 = 13 • 17 + 10
17 = 1 • 10 + 7
10 = 1 • 7 + 3
7 = 2 • 3 + 1
⇒ 1 = 68 • 17 - 5 • 231
Then
68 • 17 - 5 • 231 ≡ = 68 • 17 ≡ 1 (mod 231)
so that y = 68.