Total marbles = 2 + 7 = 9
P(Purple, then white) = (7/9)(2/8) = 7/36
Answer: 7/36
Area of semicircle = (πr²) ÷ 2
Area of semicircle:
= (3.14)(2)² ÷ 2
= (3.14)(4) ÷ 2
= 12.56/2
= 6.28
9 because when you subtract the amount of poster money from the total ($19.35), you get $14.85. $14.85 divided by $1.65 is 9, which means he bought 9 notebooks.