X is the undefined variable hope it helps
4.4 .
there is 5280 feet per mile. Meaning there is 15840 feet in three miles. Divide 15840 feet by 60(number of minutes in an hour and you get 264 , which is how many feet per minute. Divide 264 by 60(number of seconds in a minute) and you get 4.4, the number of feet per second
Assuming your question can be rewritten as:
"What number is 10% greater than 7,962"
7962 * 110% = itself + 10%
= 7962 * 1.10 <----- (1.10 = 110%)
= 8758.2
Let, the speed of boat = x
Speed of current = y
So, x + y = 280/7
x + y = 40 ---- first equation
x - y = 280/14
x - y = 20
x = 20 + y
Substitute this value of x in first equation,
20 + y + y = 40
2y = 40 - 20
y = 20/2
y = 10
Substitute this in first equation,
x + 10 = 40
x = 30
In short, Speed of Boat = 30 mph, & speed of current = 10 mph
Hope this helps!
<span>d. suppose you have run the regression and afterward you want to introduce another orthogonal variable, say, xk 1 into the model. do you have to recompute all the previous coefficients 1 to k? why or why not?</span>