PSLEFred had 3.7 m of ribbon. He used some of it to make the figure as shown.
- How much of the ribbon did Andy use to make the figure? Leave your answer in the simplest form in terms of a.
- If a = 30, how much of the ribbon was not used to make the figure? Leave your answer in meters.
(a)
Total length of ribbon used
= a + a + a + (2a - 5) + (a + 16)
= a + a + a + 2a + a - 5 + 16
= (6 a + 11) cm
(b)
1 m = 100 cm
3.7 m = 370 cm
Total length of ribbon used if a = 30
= 6 a + 11
= 6(30) + 11
= 180 + 11
= 191 cm
Total length of ribbon not used
= 370 - 191
= 179 cm
1 cm = 0.01 m
179 cm = 1.79 m
Answer(s): (a) (6a + 11) cm; (b) 1.79 m