PSLEJeremy had 2.7 m of thread. He used some of it to make the figure as shown.
- How much of the thread did Andy use to make the figure? Leave your answer in the simplest form in terms of j.
- If j = 21, how much of the thread was not used to make the figure? Leave your answer in meters.
(a)
Total length of thread used
= j + j + j + (2j - 10) + (j + 12)
= j + j + j + 2j + j - 10 + 12
= (6 j + 2) cm
(b)
1 m = 100 cm
2.7 m = 270 cm
Total length of thread used if j = 21
= 6 j + 2
= 6(21) + 2
= 126 + 2
= 128 cm
Total length of thread not used
= 270 - 128
= 142 cm
1 cm = 0.01 m
142 cm = 1.42 m
Answer(s): (a) (6j + 2) cm; (b) 1.42 m