Math Question help plz

<ol>
<li><p>The output at a factory was 40 chairs per hour for the first 3 hours of an 8-hour shift. The output then increased to 60 chairs per hour for the remainder of the 8-hour shift. What was the average (arithmetic mean) number of chairs produced per hour during this shift.</p></li>
<li><p>In a certain parking lot that contains 200 cars, 50 percent of the cars are red, 60 percent are four-doors cars, and 70 percent have alloy rims. What is the greatest number of cars in the parking lot that could be green two-door cars with alloy rims.</p></li>
</ol>

<p>52.5 and 60?</p>

<p>80 for second i mean.</p>

<p>I got the same answers, 52.5 and 80, but i wasn’t sure if it was correct. Thx anyway :D</p>

<p>Yeah you’re right. The first question is a weighted average and the second is more just logic.</p>

<p>The 2nd question doesn’t even say what percent are green or 2-door, but, of course, assuming the rest of the percentage for the two properties red and 4-door are the ones being asked about, you get 80 as an answer.</p>

<p>I was a bit confused because I got 40% for number two, but then I realized it’s out of 200 cars. Well, kind of a useless, post but I concur. 52.5 and 80 respectively.</p>

<p>1) [(40<em>3) + (60</em>5)]/8 = 52.5
2) The most exclusive group is the 2-door, which only 40% of cars can be. 0.4 * 200 = 80;</p>

<p>Q.E.D.</p>