Answer: the rate of the jet in still air is 685 mph and the rate of the jetstream is 75 mph
Step-by-step explanation:
Let x represent the rate of the jet in still air.
Let y represent the rate of the jet jetstream.
Distance = speed × time
Flying against the jetstream, a jet travels 3050 miles in 5 hours. This means that the total speed of the jet would be (x - y) mph. Therefore,
3050 = 5(x - y)
3050/5 = x - y
x - y = 610 - - - - - - - - - - - - - -1
Flying with the jetstream, the same jet travels 3800 miles in 4 hours. This means that the total speed of the jet would be (x + y) mph. Therefore,
3800 = 4(x + y)
3800/5 = x + y
x + y = 760 - - - - - - - - - - - - - -2
Adding equation 1 to equation 2, it becomes
2x = 1370
x = 1370/2 = 685mph
Substituting x = 685 into equation 1, it becomes
685 - y = 610
y = 685 - 610 = 75mph
An = a1 * r^(n-1)
-405 = -5*3^(n-1)
3^(n-1) = 81
3^4 = 81 so n-1 = 3 and n = 4
Sn = S4 = -5 (1 - 3^4) / ( 1 - 3) = 400 / -2 = -200 Answer
Answer:
You didn't say which two answers to choose from but they could possibly be 5^-4, (1/5)^4
Step-by-step explanation:
<h3>
Explanation:</h3>
In the graph x-coordinate represents the number of wind chimes sold and y-coordinate represents the profit Madison earned. If a point is below the x-axis, means it has negative y-coordinate than it represents loss. Points above x-axis should have x-coordinate more than 6 as stated in the question that she started earning profit after selling her first 6 wind chimes. All the points having x-coordinate less than 6 should lie on or below the x-axis.
By the above statement point B is completely wrong. Point C and Point A are also wrong as they both x-coordinate more than 6 but still they are below x-axis.
Point D is the makes most sense here as it has x-coordinate more than 6 and it is above x-axis. This means that when Madison sold 7 wind chimes she was in a profit of $3.75.