PSLEGeorge had 2.8 m of wire. He used some of it to make the figure as shown.
- How much of the wire did Andy use to make the figure? Leave your answer in the simplest form in terms of r.
- If r = 13, how much of the wire was not used to make the figure? Leave your answer in meters.
(a)
Total length of wire used
= r + r + r + (2r - 10) + (r + 14)
= r + r + r + 2r + r - 10 + 14
= (6 r + 4) cm
(b)
1 m = 100 cm
2.8 m = 280 cm
Total length of wire used if r = 13
= 6 r + 4
= 6(13) + 4
= 78 + 4
= 82 cm
Total length of wire not used
= 280 - 82
= 198 cm
1 cm = 0.01 m
198 cm = 1.98 m
Answer(s): (a) (6r + 4) cm; (b) 1.98 m