Online SAT course questions (math)

Test Preparation SAT Preparation
1

<ol>
<li><p>The graph of the function y=x^2+1 is shown in the xy -plane above. What is the length of segment AP. (In the diagram shown they have A as the vertex of the parabola and P as a point on the right hand side of the parabola with the coordinates (3,t)). I got the t coordinate to be 10 (which was correct), but my mistake was using the pythogrean theorem to find the length of the segment AP. Why is this incorrect to do?</p></li>
<li><p>A chemist has a solution consisting of 6 ounces of propanol and 18 ounces of water. She wants to change the solution to 40 percent propanol by adding x ounces of propanol. Which of the following equations could she solve in order to determine the value of x?</p></li>
</ol>

<p>Answer is 6+x /24+x = 40/100. How?</p>

2

<ol>
<li>Did you have the coordinate of the vertex as (0, 1)?</li>
</ol>

<p>Distance from (0,1) to (3,10) should be 3root10.</p>

<ol>
<li>Percentage questions are rely on the knowledge of the ratio: “part/whole”</li>
</ol>

<p>Currently, the part is “6 ounces of propanol”
and the whole is “18 ounces of water” + “6 ounces of propanol”</p>

<p>aka 6/24</p>

<p>When you add more propanol, you have to add it to the part and to the whole, hence</p>

<p>6+x / 24+x.</p>