The answer you are looking for would be 63.
63 is greater than 60, but less than 70, and the tens place (6) is double the ones place (3). Thus meaning 63 is the answer.
I hope this helps!
Step-by-step explanation:

Answer:
a) 320 students
b) 25 students
Step-by-step explanation:
Number of 18-years old in the survey:
(We add all frequency points for each line)
0 + 30 + 20 + 60 + 70 + 40 + 60 + 40 + 0 = 320 students
Number of 18 year old spending between 25 and 35 minutes: 40 + 65 = 105
Number of 12 year old spending between 25 and 35 minutes: 30 + 50 = 80
105 - 80 = 25 students
She'll have traveled approximately 431.07 km in 8.5 hours, also, 267.85448 miles per hour.
Given that half of the personal music players sold by a particular brand have a flaw. If the player has the flaw, it dies in the first six months. If it does not have this flaw, then only 20% fail in the first six months.
Let A be the event that it fails in I 6 months
B1 = it has a flaw
B2 = it does not have a flaw
B1 and B2 are mutually exclusive and exhaustive
the chances that it has this flaw
=The probability that it has the flaw is