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Finding the Fourth Proportional to 499.14, 688.78 and 278.08

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Solution

The fourth proportional to 499.14, 688.78 and 278.08 is: 383.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.14 : 688.78 = 278.08 : x
  2. Step 2: Convert to fraction form
    499.14/688.78 = 278.08/x
  3. Step 3: Cross multiply
    499.14x = 688.78 × 278.08
  4. Step 4: Simplify right side
    499.14x = 191,535.94
  5. Step 5: Solve for x
    x = 191,535.94/499.14
  6. Step 6: Final answer
    x = 383.73

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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.