PSLEVaidev had 3.1 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 b.
- If b = 23, how much of the thread was not used to make the figure? Leave your answer in meters.
(a)
Total length of thread used
= b + b + b + (3b - 4) + (b + 14)
= b + b + b + 3b + b - 4 + 14
= (7 b + 10) cm
(b)
1 m = 100 cm
3.1 m = 310 cm
Total length of thread used if b = 23
= 7 b + 10
= 7(23) + 10
= 161 + 10
= 171 cm
Total length of thread not used
= 310 - 171
= 139 cm
1 cm = 0.01 m
139 cm = 1.39 m
Answer(s): (a) (7b + 10) cm; (b) 1.39 m