What problem would be created by using classes of 60-120, 120-can someone explain ?

  Class boundaries need to be defined so that a point on the boundary is unambiguously placed in one class or the other. With these boundaries, a value of 120 might be placed in the first or the second class—we don't know which.

It is customary to define class boundaries between data values 60.5–120.5, for example, so that no data value can fall on the boundary, or as a semi-open interval [60, 120), so that a boundary value is clearly placed into a specific class.

idk i would have to be there to under stand it

step-by-step explanation:

idk i would have to be there to under stand it

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.