PSLEFred had 3.1 m of streamer. He used some of it to make the figure as shown.
- How much of the streamer did Andy use to make the figure? Leave your answer in the simplest form in terms of r.
- If r = 15, how much of the streamer was not used to make the figure? Leave your answer in meters.
(a)
Total length of streamer used
= r + r + r + (2r - 7) + (r + 14)
= r + r + r + 2r + r - 7 + 14
= (6 r + 7) cm
(b)
1 m = 100 cm
3.1 m = 310 cm
Total length of streamer used if r = 15
= 6 r + 7
= 6(15) + 7
= 90 + 7
= 97 cm
Total length of streamer not used
= 310 - 97
= 213 cm
1 cm = 0.01 m
213 cm = 2.13 m
Answer(s): (a) (6r + 7) cm; (b) 2.13 m