Internation SAT Math question !

Test Preparation SAT Preparation
1

<ol>
<li>If a = 2^2 x 3 x 5 and b = 2 x 3^2 x 5^2, which of the following is the largest factor of both a and b ?</li>
</ol>

<p>A. 2^2 x 3^2 x 5^2
B. 2 x 3 x 5
C. 2^2 x 5
D. 2 x 5^2
E . 2 x 3^2 </p>

<ol>
<li>In the xy-plane, the coordinates of the four vertices of a rectangle are (-3, -2), (-3, 2 ), (3, -2) and (3, 2). How many points whose X and Y coordinates are both integers are in the interior of the rectangle ? </li>
</ol>

<p>A, 8
B. 15
C. 21
D. 30
E. 35 </p>

<ol>
<li>X = (2, 4 , 5, 7, 8, 10)
Y = ( 7, 8, 12, 13, 14) </li>
</ol>

<p>In thes two sets above, how many numbers that are in set X are not in set Y ?</p>

<p>A. One
B. Two
C. Three
D. Four
E. Five </p>

<ol>
<li>A canister contains only red, blue and green gum balls. There are 24 red gum balls and the number of blue gum balls is twice the number of green gum balls. If the probability of randomly selecting a green gum ball is 1/5, how many green gum balls are in the canister ?</li>
</ol>

<p>A. 8
B. 16
C. 12
D. 16
E. 63</p>

2

<p>B-B-D-C 100 % sure</p>

3

<p>Can you please post how you solved them ?</p>

4

<p>yes, Shawki is correct</p>

5

<ol>
<li>you can just factor them if you can’t directly see it
A:2,2,3,5
B:2,3,3,5,5</li>
</ol>

<p>2.i didn’t do this one</p>

<ol>
<li>In X, 7 and 8 are also in Y, so 2,4,5,10 are not</li>
</ol>

<p>4.Let X represent the green balls, and 2X the blue.</p>

<p>24+2X+X=24+3X (the total outcome)</p>

<p>probability of green: X/24+3X =1/5</p>

<p>cross multiply and X=12</p>

6

<p>Easier way for 4 is green balls probability is 1/5 so the blues’ would be 2/5 which makes the red also 2/5 so no. of blue balls = no. of red balls and green is the half of either</p>