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Finding the Fourth Proportional to 487.40, 660.15 and 487.40

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Solution

The fourth proportional to 487.40, 660.15 and 487.40 is: 660.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.40 : 660.15 = 487.40 : x
  2. Step 2: Convert to fraction form
    487.40/660.15 = 487.40/x
  3. Step 3: Cross multiply
    487.40x = 660.15 × 487.40
  4. Step 4: Simplify right side
    487.40x = 321,757.11
  5. Step 5: Solve for x
    x = 321,757.11/487.40
  6. Step 6: Final answer
    x = 660.15

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Why These Related Problems?

These problems maintain the same ratio (1.35) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.