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Finding the Fourth Proportional to 485.05, 727.58 and 311.80

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Solution

The fourth proportional to 485.05, 727.58 and 311.80 is: 467.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.05 : 727.58 = 311.80 : x
  2. Step 2: Convert to fraction form
    485.05/727.58 = 311.80/x
  3. Step 3: Cross multiply
    485.05x = 727.58 × 311.80
  4. Step 4: Simplify right side
    485.05x = 226,859.44
  5. Step 5: Solve for x
    x = 226,859.44/485.05
  6. Step 6: Final answer
    x = 467.70

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.