PSLEIan had 2.3 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 = 16, 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 - 8) + (r + 13)
= r + r + r + 2r + r - 8 + 13
= (6 r + 5) cm
(b)
1 m = 100 cm
2.3 m = 230 cm
Total length of wire used if r = 16
= 6 r + 5
= 6(16) + 5
= 96 + 5
= 101 cm
Total length of wire not used
= 230 - 101
= 129 cm
1 cm = 0.01 m
129 cm = 1.29 m
Answer(s): (a) (6r + 5) cm; (b) 1.29 m