3x-50=7x+80
I think this is correct! Hope I helped!
Answer:
Step-by-step explanation:
Know that: 
Starting for (0,0) count how many times you go up to the marked line (which is 2)
The [+] 2 is where you would start off at on the graph, with 1/2 being the slope go up one and over two.
Answer:
Part (a) The value of Z is 0.10396. Part (b) The value of Z is 0.410008.
Step-by-step explanation:
Consider the provided information.
Part (a)
In order to find the number z such that the proportion of observations that are less than z in a standard Normal distribution is 0.5414, simply find 0.5414 in the table and search for the appropriate Z-value.
Now, observing the table it can be concluded that the value of Z is 0.10396.
Part (b)
Consider the number 65.91%
The above number can be written as 0.6591.
Now, find 0.6591 in the table and search for the appropriate Z-value.
By, observing the table it can be concluded that the value of Z is 0.410008.
Answer:
Speed of plane in still air: 490 mile/hour
speed of wind: 70 mile/hour
Step-by-step explanation:
still speed = x wind speed = w
with wind: speed = still + wind
(x+w) * 3 = 1680 ...a
against wind: speed = still - wind
(x-w) * 4 = 1680 ...b
b-a ... 4x-4w-3x-3w = 0
x-7w = 0
x = 7w
substitution: (7w+w)*3 = 1680 8w = 560 wind speed (w) = 70
still speed (x) = 7w = 490 mile/hour
