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Finding the Fourth Proportional to 498.11, 687.32 and 288.28

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Solution

The fourth proportional to 498.11, 687.32 and 288.28 is: 397.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.11 : 687.32 = 288.28 : x
  2. Step 2: Convert to fraction form
    498.11/687.32 = 288.28/x
  3. Step 3: Cross multiply
    498.11x = 687.32 × 288.28
  4. Step 4: Simplify right side
    498.11x = 198,140.61
  5. Step 5: Solve for x
    x = 198,140.61/498.11
  6. Step 6: Final answer
    x = 397.78

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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.