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Finding the Fourth Proportional to 499.16, 688.85 and 278.09

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Solution

The fourth proportional to 499.16, 688.85 and 278.09 is: 383.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.16 : 688.85 = 278.09 : x
  2. Step 2: Convert to fraction form
    499.16/688.85 = 278.09/x
  3. Step 3: Cross multiply
    499.16x = 688.85 × 278.09
  4. Step 4: Simplify right side
    499.16x = 191,557.46
  5. Step 5: Solve for x
    x = 191,557.46/499.16
  6. Step 6: Final answer
    x = 383.76

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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.