13/90 slang meaning?

13/90 = Blacks are 13% of the US population and commit 90% of crimes.

What it implies is that 13% of the US population (black people are ) committing 90% of the crimes

You all have it wrong. The reference is to the fact that blacks make up 13 percent of the population, but commit 90 percent of "interracial crime".

black lives matter = black KKK!!! the most RACIST HATE GROUP EVER!!!

13/90: A hyperbolic reference to the fact that blacks make up only 13% of the US population but commit the vast majority of all violent crime. In reality, young black males (age 13-40) make up about 3% of the population and are responsible for about 57% of violent crime. 13/90 is an exaggeration used to make a point about the disproportionate rate at which blacks commit violent crime.

13/90 is not a "term". It is a summary of the Federal Bureau of Investigation (FBI) statistical compilation of violent crime by racial composition. You can guess the rest, by paying attention to your nightly news at a local level. At a national level, such news gets white-washed.

It means the U.S.A. is the most racist country in the world....and proud of it!

It means this Country is in serious trouble and is too blind to see the problem for what it is.

13% of the US population (African-American) commits 90% of violent crime

13% of the US population commits 90% of violent crime in the US.