Answer:-5
Step-by-step explanation:
You need to distribute on both sides so u get
9c-15=20-2c
Move variable to left side and change the sign
-9c+2c-15=20
Move constant to right side and change the sign
-9c+2c=20+15
Connect like terms
-7c=35
Divide
C=-5
140 tickets sold at the door
Step by Step Explanation:
x = tickets sold in advance
y = tickets sold at the door
We use the formula ax+by=c and a+b=c
x + y = 514
17x + 20y = 9158
y = 514 - x
17x + 20(514 - x)
17x + 10,280 - 20x = 9,158
-3x + 10,280 = 9,158
-3x = -11222
x = 374
This is for tickets sold in advance so we need to find y
374 + y = 514
y = 140
140 tickets were sold at the door
Answer:
(B) The correct interpretation of this interval is that 90% of the students in the population should have their scores improve by between 72.3 and 91.4 points.
Step-by-step explanation:
Confidence interval is the range the true values fall in under a given <em>confidence level</em>.
Confidence level states the probability that a random chosen sample performs the surveyed characteristic in the range of confidence interval. Thus,
90% confidence interval means that there is 90% probability that the statistic (in this case SAT score improvement) of a member of the population falls in the confidence interval.
Answer:
0.000408163265306
Step-by-step explanation:
ITS SIMPLE JUST CACULATE IT
