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A rod is colored as follows: 1/10 is red, 1/20 is orange, 1/30 is yellow, 1/40 is green, 1/50 is blue, 1/60 is black. The remaining portion is violet, measuring 12.08 meters. What is the total length of the rod?
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Solution: Step 1: Calculate the total fraction of the rod covered by the specified colors.
Total colored fraction = 1/10 + 1/20 + 1/30 + 1/40 + 1/50 + 1/60
Step 2: Find the Least Common Multiple (LCM) of the denominators (10, 20, 30, 40, 50, 60).
LCM(10, 20, 30, 40, 50, 60) = 600.
Step 3: Convert each fraction to have the common denominator and sum them.
(60/600) + (30/600) + (20/600) + (15/600) + (12/600) + (10/600)
= (60 + 30 + 20 + 15 + 12 + 10) / 600
= 147 / 600
Step 4: Calculate the fraction of the rod that is violet.
Violet fraction = Total length (1) - Total colored fraction
Violet fraction = 1 - 147/600 = (600 - 147) / 600 = 453/600
Step 5: Use the given length of the violet part to find the total length of the rod.
Let the total length of the rod be L.
(453/600) × L = 12.08 m
L = 12.08 × (600 / 453)
L = 12.08 × (200 / 151) (by dividing 600 and 453 by their GCD, 3)
L = (1208 / 100) × (200 / 151)
L = (1208 / 151) × (200 / 100)
L = 8 × 2 (since 1208 / 151 = 8)
L = 16 m.
The total length of the rod is 16 meters.