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Finding the Fourth Proportional to 499.87, 689.83 and 278.83

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Solution

The fourth proportional to 499.87, 689.83 and 278.83 is: 384.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.87 : 689.83 = 278.83 : x
  2. Step 2: Convert to fraction form
    499.87/689.83 = 278.83/x
  3. Step 3: Cross multiply
    499.87x = 689.83 × 278.83
  4. Step 4: Simplify right side
    499.87x = 192,343.15
  5. Step 5: Solve for x
    x = 192,343.15/499.87
  6. Step 6: Final answer
    x = 384.79

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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.