NEED HELP ASAP

Driving During a Snowstorm Claire and Chris were driving to their home in Milwaukee when they came upon a snowstorm. They drove

White raven [17]

Answer:

<u>The speed of the first 90 miles was 60 mph and the speed of the last 60 miles was 40 mph. </u>

Step-by-step explanation:

1. Let's review the information given to us to answer the problem correctly:

Distance of the trip = 150 miles

Speed of the first 90 miles of the trip = x

Speed of the last 60 miles of the trip = x - 20

Time of the trip = 3 hours

2. Find their average rate of speed during the last 60 miles.

Let's recall that the formula of speed is:

Speed = Distance/Time, therefore Time = Distance/Speed

Now, we can write our equation to solve for x, this way:

90/x + 60/(x - 20) = 3

90/x = Time of the first 90 miles and 60/(x - 20) = Time of the last 60 miles

90 (x -20 ) + 60x = 3x (x - 20) Lowest Common Denominator = x * (x -20)

90x - 1,800 + 60x = 3x² - 60x

3x² - 210x + 1,800 = 0

x² - 70x + 600 = 0 (Dividing by 3 at both sides)

Using the quadratic formula we have:

x = [- (-70) +/+ √(-70²) - 4 * 1 * 600]/2 * 1

x = [ 70 +/+ √4,900 -2,400]/2

x = [ 70 +/+ 50]/2 √2,500 = 50)

x₁ = (70 + 50)/2 = 120/2 = 60

x₂ = (70 - 50)/2 = 20/2 = 10

<u>We select X₁ that is the one that matches with our problem and therefore, the first 90 miles were driven at 60 mph and the last 60 miles at 40 mph (x - 20). </u>

8 0

3 years ago

Graph a right triangle with the two points 4,5 and -4,8

Katyanochek1 [597]

Answer:

Step-by-step explanation:

Please write points using parentheses: (4, 5) and (-4, 8}.

(4, 5) is in the 1st quadrant and (-4, 8} is in the 2nd. Reversing the order of these two points yields (-4, 8) and (4, 5). From this we can see that while moving from (-4, 8) to (4, 5) involves following a line with negative slope (because the y-coordinate decreases from 8 to 5 as the x-coordinate increases from -4 to +4). This sloping line is the hypotenuse of a right triangle. Draw a vertical line segment through (-4, 8) and a horizontal line segment through (4, 5). This hypotenuse, the vertical line segment and the horizontal line segment are the boundaries of the desired right triangle.

6 0

4 years ago

16. A telemarketer makes six phone calls per hour and is able to make a sale on 30% of these contacts. During the next two hours

Reika [66]

Answer:

a) 23.11% probability of making exactly four sales.

b) 1.38% probability of making no sales.

c) 16.78% probability of making exactly two sales.

d) The mean number of sales in the two-hour period is 3.6.

Step-by-step explanation:

For each phone call, there are only two possible outcomes. Either a sale is made, or it is not. The probability of a sale being made in a call is independent from other calls. So we use the binomial probability distribution to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$