Explanation:
- 9 feet
- 10 feet (10 ft = 10·12 in = 120 in)
- 130 inches
- 12 feet (12 ft = 12·12 in = 144 in)
- 145 inches
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Obviously, 9 < 10 < 12, so ordering by feet is easy. Then we need to figure out where the inch measurements belong.
1 foot = 12 inches, so we can figure some references to use to compare to the inch measurements.
10 feet = 10·12 in = 120 in, so 130 in is longer, by less than 1 ft.
12 feet = 12·12 in = 144 in, so 145 in is longer.
