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Finding the Fourth Proportional to 498.15, 687.27 and 288.39

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Solution

The fourth proportional to 498.15, 687.27 and 288.39 is: 397.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.15 : 687.27 = 288.39 : x
  2. Step 2: Convert to fraction form
    498.15/687.27 = 288.39/x
  3. Step 3: Cross multiply
    498.15x = 687.27 × 288.39
  4. Step 4: Simplify right side
    498.15x = 198,201.80
  5. Step 5: Solve for x
    x = 198,201.80/498.15
  6. Step 6: Final answer
    x = 397.88

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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.