Bunuel
If a>0 and b>0, and if m is a% of n and n is b% of p, then in terms of a and b, p is what percent of m?
A. 10,000ab
B. 1,000,000ab
C. 100/(ab)
D. 10,000/(ab)
E. 1,000,000/(ab)
Pick numbers, in stages. If there are three integers to be compared, I start with the second to avoid generating numbers that are too large or too small.
For percents, I avoid 100% when choosing values for "a" and "b" percents. Choosing 50% or 10% usually keeps arithmetic simpler.
Assign n = 40
a% = 50
Calculatem is a% percent of n
m is 50% of 40
m = 20
Assignb = 50%
Calculaten is b% of p
40 is 50% of 80 --> p = 80
p = 80
m = 20
p is \(\frac{80}{20}\) * 100 = 400% of m
a = 50
b = 50
All the answer choices contain ab, which = 2,500
Now the process goes very quickly.
We know ab = 2,500
We need the answer choice that yields the raw number 400. "Percent" is already in the prompt's last clause: do not divide 400 by 100 (nor "move the decimal left two places") - that trap is in the answer choices.
Answer choicesEliminate A and B without calculation. They're huge.
Eliminate C without calculation. It's a fraction whose numerator is smaller than denominator - much too small.
D. 10,000/(ab)? No.
(10,000/2,500) = 4. We need 400. D is the trap answer here.
E. 1,000,000/2,500 = 400. Correct.
Answer E