Fantastic problem!
This can be converted into a speed/distance problem.
The main stem says, at some amount, taxation in both countries would be the same.
In 1st interval:
Firstly we see,
10k of 2nd case with taxation of 1k.
10k o 1st case yields no taxation.
Now using the concept of race problems.
We need to bridge 1k gap over a difference in speed of 30%-10% = 20% = 1/5.
Thus 1k/(1/5) = 5k.
10k+5k =
15k.
This is where the taxation equals in the first interval.
Now let's take next interval:
This would be after 40k, because till 40k, 1st case is way ahead of the race of 2nd.
After 40k, speed of 2nd case(France) increases.
But 50k in 1st case and 40k in 2nd case is uneven. Let's see the taxation till 50k mark for both cases:
1st case:
40k*0.3 = 12k.
2nd case:
4k+6k = 10k.
So we have a gap of 2k to be bridged by an increase in speed of 2nd case by 10% = 0.1.
Thus 2k/0.1 = 20k.
Thus 50k+20k =
70k, is where taxations meet again.
Now both of them have different amounts as well so we can keep 15k and 70k for either of them and the sum = 15k+70k =
85k.
kevincan
In Spain, the first €10,000 of income is not taxed, but every euro of the next €40,000 of income is taxed at 30%. Every euro of income above €50,000 is taxed at 50%. In France, the first €40,000 of income is taxed at 10%, and every euro of additional income is taxed at 60%. Bruno and Theodora would pay the same amount of tax in either country.
If Bruno and Theodora have different incomes, what is the sum of their incomes?
A. €75,000
B. €80,000
C. €85,000
D. €90,000
E. €95,000