Suppose a box contains 3 defective light bulbs and 9 good bulbs. Three bulbs are chosen from the box without replacement. What is the probability that at least one of the bulbs drawn is defective?

1/4

Step-by-step explanation:

3+9=12

12/3=4

b. an equilateral triangle inscribed in a circle

step-by-step explanation:

we are given the figure of two circles having a triangle inside.

now, we know that,

"when a figure is lying inside an another figure, then the outside figure is known as circumscribed figure and the figure lying inside is referred to as the inscribed figure".

as we see that, the circles are containing the triangle completely.

thus, the circles are the circumscribed figures and the triangle is the inscribed figure.

hence, we get, 'an equilateral triangle is inscribed in a circle'.