<p>The types of math questions I hate the most are the percent ones because I can never understand when it says the "50%." Is it 50% of the first number or the second? I hate it!</p>
<p>So can someone help me with a problem like this:</p>
<p>A company produced 300 appliances in the first week of the month. Because it received additional machinery, its production increased 50% from the first week to the second week. How many appliances did the company produce the second week? (Student-Produced Response).</p>
<p>The answer is either 450 (300*.5)+300 or 600 (Half is 300). I can never figure it out....is there any tips or tricks to figure a problem like this out?</p>
<p>Another problem kind of like that. </p>
<p>(There was a chart but the data you needed to know was this)</p>
<p>Elina's height at age 6 was 45 inches.
Elina's height at age 12 was 60 inches.</p>
<p>And the question is: Elina's height at the age of 12 was what percent greater than her height at the age of 6?</p>
<p>Anyways, percentage is a ratio. You can write 50% as 0.5. Now, if it increases by 50%, you multiply it with 1.5 (1+0.5).
Second is the same. 60/45=1.333 and that is 33.33%</p>
<ol>
<li>No I’m not kidding.</li>
<li>No they teach you this in middle school.</li>
<li>At least a 650. First time was 630, second time was 620…so yeah.</li>
</ol>
<p>I know how to do percents and stuff. But when they ask like “x is how many percent greater than y” is when I get confused…IDK, maybe I’m just over thinking the questions.</p>
<p>Edit: Maybe what I was confused on wasn’t clear enough.</p>
<p>I meant like in the first problem I think of it two ways. </p>
<ol>
<li>Half of 600 (Second week) is 300. Half is 50%.</li>
<li>Half of 300 is 150. So 300 + 150 = 450.</li>
</ol>
<p>Like I know how do to the problems, I can never figure out which numbers to use.</p>
<p>This is just reading the question incorrectly. The company made 300 the first week, and the second week it made 50% more than that. That’s clearly (300 x .50) + 300. The way you’re saying it doesn’t make any sense – if the company produced 300, and it increased production 50% from that, then why would it create 300 more?</p>
<p>Not so euphemistically, you suggested I was intending to insult the OP. Rather, I was asking a sincere question whose answer escaped me. It does change something, the rather important something that is intent.</p>
<p>Here is the easiest way to do this type of problem. Set up a formula which you can always reuse.</p>
<p>(Larger - Smaller) / Original</p>
<p>In this case: (60 - 45) / 45 = .333 repeating. Multiply it by 100 to get 33.3% (C). If you have to specify increase or decrease: if the larger number is the 2nd number, it’s an increase. If the larger number is the 1st number, it’s a decrease.</p>
<p>When reading the question and it says increased in it you know that it is going to go up, unless the percent is negative but that usually won’t happen so…</p>
<p>Percent changes are traditionally expressed in terms of the STARTING value. So suppose we say your savings account balance increased by 20%. We mean, find 20% of the ORIGINAL value and then add it to the original value.</p>
<p>We DON’t mean: it increased until the difference was 20% of the final value.</p>
<p>So as you have seen: 50% of 300 is 150, add it on.</p>
<p>NOT: When it reaches 600, then 300 was 50% of that final value.</p>
<p>Actually, if I were trying to write an obnoxious problem, I might ask something like the second way, since it goes against what is usually taught…</p>
<p>“A stock increased in value over a three day period. The increase in value each day was 20% of that days closing price. If the final closing price was $120, what was the value at the start of the three day period”.</p>