PSLEFred had 3.6 m of string. He used some of it to make the figure as shown.
- How much of the string did Andy use to make the figure? Leave your answer in the simplest form in terms of j.
- If j = 23, how much of the string was not used to make the figure? Leave your answer in meters.
(a)
Total length of string used
= j + j + j + (3j - 8) + (j + 18)
= j + j + j + 3j + j - 8 + 18
= (7 j + 10) cm
(b)
1 m = 100 cm
3.6 m = 360 cm
Total length of string used if j = 23
= 7 j + 10
= 7(23) + 10
= 161 + 10
= 171 cm
Total length of string not used
= 360 - 171
= 189 cm
1 cm = 0.01 m
189 cm = 1.89 m
Answer(s): (a) (7j + 10) cm; (b) 1.89 m