Respuesta :

Answer:

40cm

Step-by-step explanation:

Piece of string is 64cm.

Divided in the ratio 1 : 2 : 5

Assuming 1x, 2x, and 5x as the pieces

Then,

⇒ 1x + 2x + 5x = 64

⇒ 8x = 64

⇒ 8x/8 = 64/8 [dividing both sides by 8]

⇒ x = 8

Henceforth, lenght of the longest piece would be 5x = 5(8) = 40cm