PSLESam had 2.9 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 r.
- If r = 13, how much of the string was not used to make the figure? Leave your answer in meters.
(a)
Total length of string used
= r + r + r + (2r - 6) + (r + 14)
= r + r + r + 2r + r - 6 + 14
= (6 r + 8) cm
(b)
1 m = 100 cm
2.9 m = 290 cm
Total length of string used if r = 13
= 6 r + 8
= 6(13) + 8
= 78 + 8
= 86 cm
Total length of string not used
= 290 - 86
= 204 cm
1 cm = 0.01 m
204 cm = 2.04 m
Answer(s): (a) (6r + 8) cm; (b) 2.04 m