Adam has a thread which is 470 cm long.
He cuts the thread into 3 pieces.
The first piece is 4 times as long as the second piece.
The third piece is 420 cm long.
- Find the total length of the first and third pieces.
- Find the difference in length between the second and the third piece.
(a)
Focus on the sentence with the word '
times'.
Assign 1 u to the variable that is found after the word '
times'.
Length of second piece = 1 u
Length of first piece = 4 u
Length of third piece = 420 cm
Length of the second and the third pieces
= 470 - 420
= 50 cm
4 u + 1 u = 50
5 u = 50
1 u = 50 ÷ 5 = 10
Total length of the first and third pieces
= 4 u + 420
= 4 x 10 + 420
= 40 + 420
= 460 cm
(b)
Difference in length between the second and the third piece
= 420 - 10
= 410 cm
Answer(s): (a) 460 cm; (b) 410 cm