What range show my BP be in. 50 year old black

There isn't really a normal blood pressure, there is a continuum of blood pressures among ppl at any age (for example, 50). By age 50, about 1/2 of Americans will have a blood pressure that is higher than what cardiovascular disease prevention guidelines have set as targets.
The goal blood pressure for a 50 year old person without any other medical issues is <140/90. People at higher risk of developing cardiovascular disease have correspondingly lower blood pressure targets. People with kidney disease, diabetes or prediabetes (also known as metabolic syndrome), and those with known cardiovascular disease (heart failure or previous heart attack) should have a target blood pressure of <130.80.
(from answers.com)

What your BP monitor says.