Answer:
d/4 + d/6=45/60 hours=3/4 hoursStep-by-step explanation:
3d+2d=12 x 3/4=9
5d=9
d=9/5 km ……………….
Answer:
Go to the bottom of that problem and click save for later
Answer:
x = 3 or -3
Step-by-step explanation:
So you have the equation x² - 9 = 0
Move the 9 to the other side: x² = 9
Then take the square root of both sides: 
= ±
x = ± = ±3
x = 3 or -3
Answer:
ur answer is 9
Step-by-step explanation:
Answer:
it saves 2.5 minutes
Step-by-step explanation:
The expected value of a random variable is the sum of products of possibilities and the probability of each.
Here, you have a probability of 0.9 of saving 5 minutes, and a probability of 0.1 of adding 20 minutes.
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The expected value of the shortcut is ...
0.9(-5) +0.1(20) = -4.5 +2.0 = -2.5
The shortcut is expected to save 2.5 minutes on average.
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<em>Additional comment</em>
The probability of 0.9 comes from the 9 of 10 trips that result in a time saving.
