EASY 7TH GRADE MATH 6 out of 8 dentists recommend crest. In a group of 156 dentists, how many of them recommend crest?

117

Step-by-step explanation:

6/8   x/156 so 156/8=19.5*6=117

90 degree

Step-by-step explanation:

Three points A, B, and C are added and shown in attached picture.

As the property of inscribed angle in circle:

angle BAC = (1/2) x 88 = 44 deg

As the property of complement angle:

angle ABC = 180 - 89 = 91 deg

As the property of sum of three angles in a triangle:

angle ACB + angle ABC + angle BAC = 180 deg

=> angle ACB = 180 - angle ABC - angle BAC = 180 - 44 - 91 = 45 deg

One more time, we use the property of inscribed angle in circle:

x = 2 x angle ACB = 2 x 45 = 90 deg

Hope this helps!