Remove padding and have the block centered?

Question

css

I can't figure out how to remove the indent and have the block centered?
When I remove "margin-right: 5.5%;" and put "margin-right: 0;"

Then there is no indentation, but the right block runs away to the left.
Please tell me how to make it centered and without indents between blocks A and B
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Website: https://pikcha.pw/052017-2/

Answer 1

margin-right: 0;
width: 50%

Answer 2

the block on the left has margin-right and the width is set.
do this in the browser

margin-right: 0;
width: 52.75%;

got this picture: prntscr.com/iwm2zh