Here, the distance traveled is not given, but Irina's bike-riding speed is: it is 16 mph.
Let the distance traveled be d. Then d = (27 mph)(0.4 hr) = 10.8 miles.
By bicycle, distance = rate times time. Here, 10.8 miles = (16 mph)(time), and so
10.8 mi
time = --------------- = 0.675 hour (40.5 minutes).
16 mph
Answer:
900 cubic units
Step-by-step explanation:
V= base area *height of prism
Area of base is 1/2*15*8 =60
V=60*15
V=900
Answer:
2nd debate was 3 hours long.
Step-by-step explanation:
We have been given that during the mayoral election,two debates were held between the candidates. The first debate lasted 1 2/3 hours. The second one was 1 4/5 times as long as the first one.
Let us find the estimate of time spent on 2nd debate.
1 2/3 hours would be approximately 2 hours. 1 4/5 times would be equal to 2 times.

Therefore, the estimated time is less 4 hours.
To find the time spent on 2nd debate, we will multiply 1 2/3 by 1 4/5.
First of all, we will convert mixed fractions into improper fractions as:


Now, we will multiply both fractions as:



Therefore, the 2nd debate was 3 hours long.
Answer:
The reason why standard deviation of the entire class is greater than standard deviation of males and females considered separately, is that mean values for males and females are different from each other.
Step-by-step explanation:
The concept of mean is well represented by the following formula
mean =
, where x1, x2, xn are the observations and N is the number of observations (population).
Standard deviation represents the distance between each observation and the mean of the population (all observations). The formula for this parameter is:
Standard deviation =√[((x1 - x)² + (x2-x)² + ....+ (xn-x)²)/N-1], where x1, x2,..., xn are the observations and x is the mean value.
In this case you have that each height registered is an observation and the number of observations represents the N value. As you can see if the mean for males is different from that of females their standard deviation will be different too. Usually males have heigths greater than that of females (1.77 vs 1.64, in USA for example), and heights inside each group will be more similar than between groups. Then, when you mix all observation there will be an increase in standard deviation, because you are mixing very different heigths