PSLEIan had 3.4 m of string. He used some of it to make the figure as shown.
- How much of the string did Andy use to make the figure? Leave your answer in the simplest form in terms of w.
- If w = 21, how much of the string was not used to make the figure? Leave your answer in meters.
(a)
Total length of string used
= w + w + w + (2w - 8) + (w + 11)
= w + w + w + 2w + w - 8 + 11
= (6 w + 3) cm
(b)
1 m = 100 cm
3.4 m = 340 cm
Total length of string used if w = 21
= 6 w + 3
= 6(21) + 3
= 126 + 3
= 129 cm
Total length of string not used
= 340 - 129
= 211 cm
1 cm = 0.01 m
211 cm = 2.11 m
Answer(s): (a) (6w + 3) cm; (b) 2.11 m