Answer:
$5,250
Step-by-step explanation:
2/7x - [4/5(2/7x)] = 300
2/7x - 8/35x = 300
10/35x = 8/35x = 300
2/35x = 300
2x = 10500
x = 5250
Answer:
The answer is 448 seconds
Step-by-step explanation:
Answer:
0.7698
Step-by-step explanation:
If you call your random variable 
, then what you are looking for is
because you want the probability of being <em>between 87 and 123.</em>
We need a table with of the normal distribution. But we can only find the table with 
and 
. Because of that, first we need to <em>normalize </em>our random variable:
(you can always normalize your variable following the same formula!)
now we can do something similar to our limits, to get a better expression:
And we transform our problem to a simpler one:
(see Figure 1)
From our table we can see that 
(this is represented in figure 2).
Remember that the whole area below the curve is exactly 1. So we can conclude that 
(because 0.8849 + 0.1151 = 1). We also know the normal distribution is symmetric, then
.
FINALLY:
Let's solve your equation step-by-step.
<span>0=<span>4+<span>n/5
</span></span></span>Step 1: Simplify both sides of the equation.<span>0=<span><span><span>1/5</span>n</span>+4
</span></span>Step 2: Flip the equation.<span><span><span><span>1/5</span>n</span>+4</span>=0
</span>Step 3: Subtract 4 from both sides.<span><span><span><span><span>1/5</span>n</span>+4</span>−4</span>=<span>0−4
</span></span><span><span><span>1/5</span>n</span>=<span>−4
</span></span>Step 4: Divide both sides by 1/5.<span><span><span><span>1/5</span>n/</span><span>1/5 </span></span>=<span><span>−4/</span><span>15</span></span></span><span>n=<span>−20
</span></span>Answer:<span>n=<span>−<span>20</span></span></span>
