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Finding the Fourth Proportional to 498.60, 687.42 and 387.87

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Solution

The fourth proportional to 498.60, 687.42 and 387.87 is: 534.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.60 : 687.42 = 387.87 : x
  2. Step 2: Convert to fraction form
    498.60/687.42 = 387.87/x
  3. Step 3: Cross multiply
    498.60x = 687.42 × 387.87
  4. Step 4: Simplify right side
    498.60x = 266,629.60
  5. Step 5: Solve for x
    x = 266,629.60/498.60
  6. Step 6: Final answer
    x = 534.76

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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.