Speed, S = Distance (d) / Time (t) => S= d/t => t= d/S
Let the speed of boat in still water be x mph
Resulting speed upstream = x-4 mph for a distance of 30 miles
Resulting speed downstream = x-4 mph for a distance of 50 miles
Time taken in both distances is equal.
Therefore,
30/(x-4) = 50/(x+4) => 30(x+4) = 50(x-4) => 30x+120 = 50x-200 => 120+200 = (50-30)x => 20x = 320 => x=320/20 = 16 mph
The speed of boat in still water is 16 mph.
Answer:
21/41
Step-by-step explanation:
Find the total number of students
6+7+2+3+6+8+4+5=41
Then find the students that do not study chemistry
6+7+2+5 = 20
P( not study chemistry) = do not study chem)/total
=21/41
I think it’s q12 or C hope this helped
Answer:
I would reject the null hypothesis because it falls outside of the 95% confidence interval.