Answer:
-390 mph
Step-by-step explanation:
Let a and b represent, respectively, the distances of A and B from the airport. The distance d between the planes is then given by the Pythagorean theorem as ...
d² = a² + b²
Differentiating with respect to time, we have ...
2d·d' = 2a·a' +2b·b'
Solving for d', we get ...
d' = (a/d)a' +(b/d)b'
The value of d at the time of interest is ...
d = √(a² +b²) = √(30² +40²) = √2500 = 50
Then the rate of change of separation is ...
d' = (30/50)(-250 mph) +(40/50)(-300 mph) = (-150 -240) mph
d' = -390 mph
The distance between planes is decreasing at 390 miles per hour.
Answer:
X= 18; Y=15
Step-by-step explanation:
As a student myself working this out I cannot explain how I got the answer but I know it is correct.
The ratio here is
3/4 cup milk 6 cups milk
-------------------- Now equate this to -----------------
1 beaten egg x
Solving this equation, (3/4)x = 6, and x = 8 (eggs) (answer)
Check: Note that 3/4 / 1 = 6 / 8
Answer:
56%
Step-by-step explanation:
Reducing the picture by 80% and then by 70% gives a reduction of 56%
70% of 80 = 0.7 × 80 = 56%