<p>i couldnt find any solutions on the other threads..</p>
<p>the question is</p>
<p>Practice Test # 1 Section 9
10. if 30 percent of 40 percent of a positive number is equal to 20% of w percent of the same number, what is the value of w?</p>
<p>thank u guys in advance</p>
<p>anyone..? pleasE?</p>
<p>If the number is X, then
(0.3)(0.4)X = (0.2)(w/100)X
0.12 = (0.2)(0.01) w
w = 0.12 / 0.002 = 120/2 = 60</p>
<p>(Actually, you can do it even faster:
'30% of 40%' = '60% of 20%' = '20% of 60%', and this is 20% of w% ; so w = 60 )</p>
<p>k
30 percent of 40 percent of X translates to
(.3)(.4)(x)</p>
<p>The second part translates to
(.2)(W * 10 ^ -2 (remember if you have w percent the number is .0W or W * 10^-2)(X)</p>
<p>Set em equal
.12x = .02 (W) (X)
X's go away
.12 = .02 W
.12 = 2 / 100 (w)
.12 (100) / 2 = w
.6 (100) = W
W = 60</p>
<p>I may have done something wrong... but thats the jist of it.</p>
<p>This should be right:</p>
<p>.3(.4(X))=.2(w(X))
Let's pick any positive integer, 10 is usually easy to work with in percentages... [or you can notice that the Xs drop out since they are on both sides, it doesn't really matter though]</p>
<p>.12(10)=.2(w(10))
1.2=.2(10w)
w=.6</p>
<p>And to convert to percentages multiply .6 by 100 to get w=60%</p>
<p>thank you so much guys!!</p>