Question

Anthony is making a collage for his art class by picking shapes randomly. He has five squares, two triangles, two ovals, and four circles. Find P(a triangle or a square is chosen first).

Answer 1

There total quantity of shapes is 5 + 2 + 2 + 4 = 13. The total quantity of triangles and squares is 2 + 5 = 7. The probability of choosing a triangle or a square first is 7/13

Answer 2

P(a triangle or a square is chosen first)
`=(7)/(13)`

Explanation:

Probability of an outcome is the ratio of number of favorable outcome to total number of outcomes.

Total number of outcomes= 5 + 2 + 2 + 4 = 13

P(a triangle or a square is chosen first) = P(a triangle chosen first) + P(a square chosen first)

`\texttt{P(a triangle chosen first)}=\frac{\texttt{Number of triangles}}{\texttt{Total number of shapes}}=(2)/(13)`

`\texttt{P(a square chosen first)}=\frac{\texttt{Number of squares}}{\texttt{Total number of shapes}}=(5)/(13)`

`\texttt{P(a triangle or a square is chosen first) }=(2)/(13)+(5)/(13)=(7)/(13)`

P(a triangle or a square is chosen first)
`=(7)/(13)`