<p>Let’s use that example with electric bulbs, then the light might come on.
Not a formal proof, just an illustration.</p>
<p>In electric bulbs manufacturing 80% of bulbs pass the first test (A), 60% of bulbs pass two tests (A&B); what is the probability that a bulb which passed the first test will pass the second one (B)?
P(B|A) = .6/.8 = .75</p>
<p>Say, we have 100 bulbs.
We know that on average 80 bubs pass the first test, and 60 of them pass the second test. The chances to randomly pick one of those 60 bulbs out of 80 is
60/80 = .75.</p>
<p>Let z be a complex solution to the equation x^2 -2x + 2 = 0. What does this equal?
A 1
B 1.41
C 2.45
D 3
E 3.73 </p>
<p>The easiest way to solve this is simply to plug each answer into the equation and see which one works! No need to use any fancy shmancy formulas or any of that!</p>
<p>I don’t understand this least-squares regression. Does anyone have me some tips or probably a helpful website. How does one identify linear, quadratic and exponential without using a graphing calculator</p>
<p>Okay, I have the Barron’s Math Level II book and I have some questions. </p>
<p>22) In Triangle ABC, angle b is 42 degrees, angle c is 30 degrees and AB is 100. Find the length of BC. I keep getting like -93 and they say the answer is 190.2… how is that true? I looked at the explanation and followed the steps and I keep getting -93…??</p>
<p>24) In the explanation for it, it says to “backsolve to get pi over 3”. What does backsolve even mean?</p>
<p>24) It just means since you have 1.04 or whatever, logically “backsolve” to figure out that 1.04 is equivalent to pi/3. Foreward solving would get you 1.04 from pi/3. Backsolving gets you back to pi/3 from 1.04</p>
<p>Thanks a lot Latency! And btw, does anyone else think that the Barron’s Level Two Book is like impossible? Someone said that your score in Barron’s will be way lower than the actual thing like 50 pts or so. Is that true?</p>
