PSLEHoward had 2.6 m of rope. He used some of it to make the figure as shown.
- How much of the rope 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 rope was not used to make the figure? Leave your answer in meters.
(a)
Total length of rope used
= r + r + r + (3r - 8) + (r + 19)
= r + r + r + 3r + r - 8 + 19
= (7 r + 11) cm
(b)
1 m = 100 cm
2.6 m = 260 cm
Total length of rope used if r = 15
= 7 r + 11
= 7(15) + 11
= 105 + 11
= 116 cm
Total length of rope not used
= 260 - 116
= 144 cm
1 cm = 0.01 m
144 cm = 1.44 m
Answer(s): (a) (7r + 11) cm; (b) 1.44 m