PSLEFred had 3.1 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 a.
- If a = 24, how much of the rope was not used to make the figure? Leave your answer in meters.
(a)
Total length of rope used
= a + a + a + (2a - 10) + (a + 12)
= a + a + a + 2a + a - 10 + 12
= (6 a + 2) cm
(b)
1 m = 100 cm
3.1 m = 310 cm
Total length of rope used if a = 24
= 6 a + 2
= 6(24) + 2
= 144 + 2
= 146 cm
Total length of rope not used
= 310 - 146
= 164 cm
1 cm = 0.01 m
164 cm = 1.64 m
Answer(s): (a) (6a + 2) cm; (b) 1.64 m