Green Valley High School recently completed an expansion. Of the new classrooms, 11 are math classrooms, 8 are science classrooms, and 6 are history classrooms. If a single classroom is picked at random, what is the probability that the classroom is for math or history?.

d. 8

step-by-step explanation:

the given radical expression is:

we can rewrite this as:

we express as square numbers to get;

the exponents will now cancel out to give.

the correct answer is d

hey! so 1 (25) out of 4 (100) is 25 so your answer is 25%. it's like quarters!

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.