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Finding the Fourth Proportional to 499.59, 689.39 and 286.91

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Solution

The fourth proportional to 499.59, 689.39 and 286.91 is: 395.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.59 : 689.39 = 286.91 : x
  2. Step 2: Convert to fraction form
    499.59/689.39 = 286.91/x
  3. Step 3: Cross multiply
    499.59x = 689.39 × 286.91
  4. Step 4: Simplify right side
    499.59x = 197,789.44
  5. Step 5: Solve for x
    x = 197,789.44/499.59
  6. Step 6: Final answer
    x = 395.90

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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.