Find aspect ratio of rectangle made of multiple and spaced by percentage I have two rectangles with known aspect ratios:


*

*First one is 1:1

*Second one is 3:4


They're vertically stacked under each other. Finding aspect ratio of combined rectangle is easy.
BUT there is a a catch - space between vertical blocks equals to 10% of the final height (including the percentage increase itself).
For example, if the first block height is 100 units and second block height is 400 units - the total space between will NOT be (100+400) * 10% = 50, since the total height will be 550, and 50 is not 10% of 550.
Can someone assist on how to calculate this percentage? as I'm losing my mind...
Thank you.


If the gap is $10\%$ of the total height, then the actual rectangles constitute $90\%$ of the height. That means that whatever the height $h$ is, $90\%$ of it is $500$:
$$
h\cdot 90\% = 500\\
h = \frac{500}{90\%} = 555.55\ldots
$$
which makes the gap $555.55\ldots - 500 = 55.55\ldots$, which you can easily see is a tenth of the total height.
