It's almost midnight, I am about to finish my studies for the day (yup, from morning till now) and this is the problem I get:
If 125% of j is equal to 25% of k, 150% of k is equal to 50% of l, and 175% of l is equal to 75% of m, then 20% of m is equal to what percent of 200% of j ?
It's got to be a cruel joke, I have no idea how to tackle this, unless I substitute some numbers here and do the arduous work of calculating everything. But there must be a faster way. Will you please help? Last one for today, I promise.
Here is one way.
Since in the end the j is there, or a percent of j is what is asked for, then carry over the j from beginning to end.
"125% of j is equal to 25% of k,..."
1.25j = 0.25k
k = 1.25j /0.25 = 5j
"...150% of k is equal to 50% of l,..."
1.50k = 0.50L
1.5(5j) = 0.5L
L = 1.5(5j) /0.5 = 15j
"...and 175% of l is equal to 75% of m,..."
1.75L = 0.75m
1.75(15j) = 0.75m
m = 1.75(15j) /0.75 = 35j
"...then 20% of m is equal to what percent of 200% of j ?"
0.20m = x*2.00j
0.2(35j) = x(2j)
x = 0.2(35j) /2j = 3.5 = 350% ------------answer.
I see.
Math needs practice. That's why I'm here in this forum.
While in school, we may be good at the Math topics we are studying because they are "fresh" in our minds. Then out of the studying ib school, we tend to forget those topics. [It takes only about a month before I forget how to do most Math topics, by the way.]
So, you need to take it up a notch?
Practice, practice, and practice.
See and try to solve more of similar problems in the Exercises portion of your textbook.
I wonder why they call those "Exercises"?
You are absolutely right. And thanks for your input.
I am facing another problem though. I bought 4 GMAT books 3-4 months ago and I studied every single one of them every day. I had planned to study until 3-4 days before the exam, and the last 3-4 days, I had planned to take practice tests. So I studied these 4 books religiously and learned them inside and out, but now that I take the practice tests, I find the math much harder than the ones in the book. I am practicing as much as I can with the math that is in the practice tests, but in some ways, it's a bit too late.
Am not asking for sympathy of course, just wanted to put that in there just in case someone else might benefit from it.