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Finding the Fourth Proportional to 487.10, 672.90 and 387.84

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Solution

The fourth proportional to 487.10, 672.90 and 387.84 is: 535.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.10 : 672.90 = 387.84 : x
  2. Step 2: Convert to fraction form
    487.10/672.90 = 387.84/x
  3. Step 3: Cross multiply
    487.10x = 672.90 × 387.84
  4. Step 4: Simplify right side
    487.10x = 260,977.54
  5. Step 5: Solve for x
    x = 260,977.54/487.10
  6. Step 6: Final answer
    x = 535.78

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.