Given:
On the first day, she drove 650 miles in 10 hours.
On the second day, she got a later start and drove 540 miles in 8 hours.
To find:
Difference between average speed of second day and first day.
Solution:
We know that,

On the first day, she drove 650 miles in 10 hours. So, the average speed is


So, the average speed on first day is 65 miles per hour.
On the second day, she got a later start and drove 540 miles in 8 hours.


So, the average speed on second day is 67.5 miles per hour.
Difference between average speed is

Therefore, the average speed on the second day is 2.5 miles per hour is faster than first day.
Answer:
a) distance halfway = 16.49 [m], displacement halfway = 10.5 [m]
b) distrance traveled increases when the child completes one circuit of the track.
Step-by-step explanation:
a) Distance is a scalar quantity that tells you how much space a body has covered when moving. Displacement is a vector quantity that tells you how far from its initial position and object is after moving.
In this case, the child goes around the track only halfway from point 1 to point 2. We know the circunference or perimeter of a circle to be 2*PI*radius. We also know the child only when halfway, so we need to divide the perimeter by 2, thus we get distance = PI*radius
- distance halfway = (PI)*(5.25) = 16.49 [m]
And now that we know the definition of displacement, we can easily see that the child went from point 1 to point 2 which is located at a distance of 1 diameter from point 1:
- displacement halfway = D = 2*radius = 2(5.25) = 10.5 [m]
b)What happens to the distance when the child completes one circuit? The distance will increase beause he is now completing the circuit so he is covering more ground in his movement:
- distance circuit = 2*(PI)*radius = 2(PI)(5.25) = 32.99 [m]
32.99 is more than 16.49 so we are certain that the distance increases.
Answer: OPTION D.
Step-by-step explanation:
You know that Lindy's total cost can be found using this expression provided in the exercise:

Where "d" is the number of drinks she orders and "t" is the number of toppings for a medium pizza she orders.
Since she and her friends to order 4 drinks and a medium pizza with 3 toppings, you can find the total cost by substitute values into the given expression.
The values are:

Substituting into the expression and evaluating, you get:
