Answer:
= 2001.19452
Step-by-step explanation:
V=πr2h=π·72·13≈2001.19452
Answer: the rate of speed for train A is 66 miles per hour.
Step-by-step explanation:
Let x represent the speed of train B.
2 trains leave the station at the same time. Train A is traveling 16 miles per hour slower than train B. This means that the speed of train A would be x - 16 miles per hour.
The two trains are 720 miles apart after 4 hours. It means that both trains traveled a total distance of 720 miles in 4 hours.
Distance = speed × time
Distance travelled by train A after 4 hours is
4(x - 16) = 4x - 64
Distance travelled by train B after 4 hours is
4 × x = 4x
Since the total distance travelled by both trains is 720 miles, then
4x - 64 + 4x = 720
8x = 720 - 64 = 656
x = 656/8 = 82 miles per hour
The speed of train A would be
82 - 16 = 66 miles per hour.
Answer:
1. 55mph
Step-by-step explanation:
Answer:
Since the calculated value of F = 1.4397 is less than the critical value of
F (9,9)= 2.4403 we conclude that the first instructor's variance is smaller and reject H0.
Step-by-step explanation:
1)Formulate the hypothesis that first variance is equal or greater than the second variance
H0: σ₁²≥σ₂² against the claim that the first instructor's variance is smaller
Ha: σ₁²< σ₂²
2) Test Statistic F= s₂²/s₁²
F= 84.8/ 58.9= 1.4397
3)Degrees of Freedom = n1-1= 10-1= 9 and n2 = 10-1= 9
4)Critical value at 10 % significance level= F(9,9)= 2.4403
5)Since the calculated value of F = 1.4397 is less than the critical value of
F (9,9)= 2.4403 we conclude that the first instructor's variance is smaller and reject H0.
