Answer:
The expression that represents his total time is given by "t = 7.5/s" where s is his speed against the wind.
Step-by-step explanation:
In order to solve this problem we will assign a variable to Curtis speed on the first leg of the trip, this will be called "s". Since the speed on the first part is "s" and the speed on the second part is 20% higher, then the speed on the second part is "1.2s". Each leg of the course is 9 miles long, therefore the time it took to go each way is given by:
time = distance/speed
First part:
t1 = 9/s
Second part:
t2 = 9/1.2s = 7.5/s
The expression for the whole course is the sum of each, so we have:
t = t1 + t2
t = 9/s + 7.5/s
t = (9 + 7.5)/s = (16.5)/s
B is the answer hope this helps
Answer:
m = 28g
Step-by-step explanation:
Answer:
The differences become smaller
Step-by-step explanation:
Normally, we use the t-distribution table rather than the normal distribution when the population standard deviation is unknown and when the sample size is small i.e. less than 30.
Now, as the sample size gets bigger, we will be getting closer to the point where we have to use the normal distribution.
This means that as the sample size increases, the values of the t-distribution will be getting close to that of the normal distribution because normal distribution is used when sample is more than 30.
For example the t-value for a sample of 25 people would be closer to the normal distribution value for a sample of 35 people while a t-value for a sample of 15 people will be far away from the normal distribution value for a sample of 35 people.
Thus, as the sample size increases, the differences between the t-distribution and standard normal distribution becomes smaller.
Answer:
8:55 am.
Step-by-step explanation:
First we find the least Common Multiple of 25 and 35.
25 = 5 * 5
35 = 5 * 7
The LCM = 5 * 5 * 7 = 175 minutes
or 2 hours 55 minutes.
So the required time is 8:55 am.