PSLEJeremy had 2.5 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 = 18, 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 + (3j - 5) + (j + 19)
= j + j + j + 3j + j - 5 + 19
= (7 j + 14) cm
(b)
1 m = 100 cm
2.5 m = 250 cm
Total length of thread used if j = 18
= 7 j + 14
= 7(18) + 14
= 126 + 14
= 140 cm
Total length of thread not used
= 250 - 140
= 110 cm
1 cm = 0.01 m
110 cm = 1.1 m
Answer(s): (a) (7j + 14) cm; (b) 1.1 m