Respuesta :
Answer:
Step-by-step explanation:
First, simplify into the parts given by sum of ratio values.
90cm / 15 = 6 cm
(a) longest piece
= 7 x 6 = 42 cm
(b) difference between longest and shortest
shortest = 3 x 6 = 18 cm
Difference = 42 - 18 = 24 cm