Because he’s taxed by his home planet, Mork pays a tax rate of 40% on

Assume Mork income = x=> Mindy income =3x; from given equation we can write that:
Mindy tax=3*.3X=.9x; Mork Tax=.4x
Total tax=.4x+.9x=1.3x
Combined tax=1.3x/4x *100=32.5%
Hence answer is A

Thanks,

It's possible to solve such task mentally without any equations.
Difference between Mork and Mindi = 40% - 30% = 10%
In common we have 4 parts: 1 Mork + 3 Mindi
10% / 4 = 2,5% in one part.

And as Mindi has more weight in this situation, common percent will be closer to her and will be on 1 part distance and will be equal 30% + 2,5% = 32,5%
If they have equal parts 2:2, 3:3 etc combine percent will be equal to 35%
If Mork has more weight (with same ratio) than it'll be 37,5%

It looks a little convoluted but if you look at the picture and remember this approach - it can save a lot of time on average-weighted tasks.

Answer is A

VERITAS PREP OFFICIAL SOLUTION:

If your mind immediately thought “the average of 30% and 40% is 35% – C!” you’re not alone…but you may be falling for the old Mrs. Doubtfire routine, mistaking a more-difficult question for one that’s sweet, nurturing, and easy. Because Mork & Mindy don’t earn the same amount, their average must be weighted, meaning that the correct answer is A (since Mindy’s income carries 3/4 of the weight, the weighted average will be 3/4 of the way toward her income). And the lesson – when a GMAT question seems a bit too easy, don’t merely assume that it’s easy and that you’re doing poorly. Think about Mrs. Doubtfire playing soccer in the park and Aerosmith singing “Dude Looks Like Lady” (or “Hard Looks Like It’s Easy”…same rhythm) and see if you’re falling for a hard problem disguised as an easy one.

Robin Williams will be remembered for the many ways he inspired us and the many lessons he taught us. While, sadly, you won’t be able to have a conversation with him on a park bench in Boston Common, remembering his Mrs. Doubtfire character on the GMAT will help you on your quest to find similarly-inspiring professors of your own.

Thank you, O’ Captain.

We can solve this question using algebra - btw although this is minor detail, the fact that Mork and Mindy have letters that begin with the same name can be confusing- but with proper algebra we can reduce this confusion.

X(.6) - instead of using x-x(.4) which would represent a 40% decrease we can just take the opposite of 40% and multiply by the given value - Mork's income- to calculate a 40% decrease x(.6)= x- x(.4)

Y(.7) Same rule here

Yet- Mindy's income is 3 times Mork's income so we can make set up x as a constant

x(.6)
3x(.4)

$100(.6) = $60.00
$300(.7) = $210.00

1 - $270/$400 =
130/400 =
32.5%

We can create the following equation:

(0.4 x n + 0.3 x 3n)/4n = (0.4n + 0.9n)/4n = 1.3n/4n = 0.325 = 32.5%

Alternate Solution:

Let’s assume that Mork earns $100, and thus Mindy earns $300.

Mork pays 100 x 0.4 = $40 in taxes.

Mindy pays 300 x 0.3 = $90 in taxes.

Thus their combined tax rate is (40 + 90)/(100 + 300) = 130/400 = 0.325 = 32.5%.

Answer: A