The green ribbon is said to have 9 inches long
=> the red ribbon is 1/10 the length of the green ribbon
And the purple ribbon is 10 times the length of the red ribbon
Let G = green ribbon
Let R = red ribbon
and Let P = purple ribbon
G = 9 inches
R = 1/10 x 9 or equals to 9 x .10 = .9 inches
P = .9 x 10 = 9 inches
thus, the length of the purple ribbon is 10 inches.