Answer:
1a. 42% of teens spend time playing games on their phones
2a. Collecting data would be difficult because you have t figure out what state in the U.S to use.
3a. 513 students from 84 colleges nationwide found that 34.89 percent of them spend a lot of time playing games on their smartphones, and 42.69 percent play occasionally.
Probability that you will get exactly 4 tails, if you flip a fair coin 7 times is: 
Step-by-step explanation:
We need to find the probability that you will get exactly 4 tails, if you flip a fair coin 7 times.
This is the combination question.
The total combinations will be: 2^7=128
Now, finding number of ways we can get exactly 4 tiles:
We will use the formula:

in our given question, n= 7, k= 4
Putting values:

So, Probability that you will get exactly 4 tails, if you flip a fair coin 7 times is: 
Keywords: Probability
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Answer:
2 or 12
Step-by-step explanation:
The answer that we will use this equation 1/t1 +1/t2=1/ttotal
where t1 is the time of smaller pipe while t2 is the of the larger pipe
Given t total =4 while t2 is equal to t2=t1-6
So know you can solve the problem by changing it into (2t1-6)/(t1*(t1-6))=1/4
8( t1-3)=(t1^2-6t1)
t1^2-14t1+24=0
t1=2 or 12
So if you do 584/4 you get 146 which is the miles per hour, which is the rate of the jet. Also, the jet could fly 1,898 miles in 13 hours.
The formula of a volume of a cone:

We have r = 5m and H = 6m. Substitute:
