You have 10 shirts 2 of them are black what is the probability of not choosing a black shirt.

80% or 4/5

Step-by-step explanation:

the probability of not choosing a black shirt

P = number of shirts that are not black ÷ total number of shirts

Total number of shirts = 10

Number of black shirts = 2

Number of shirts that are not black = 10-2 = 8

P = 8/10 = 4/5 or 80%

second option

step-by-step explanation:

the measures of a triangle equal 180. use that to find x.

2x+3x+4x=180

9x=180

9x/9=180/9

x=20

now you know x, you know angle a is 40°, angle b is 60°, angle c is 80°.

because angle a is 40°, the first option doesn't work.

because angle b is 60°, the second option does work.

when you add angle a and b, you get 100°. complementary means it equals 90°, so the third option doesn't work.

when you add angle a and c, you get 120°, which is not 100.