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Finding the Fourth Proportional to 499.89, 689.85 and 278.84

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Solution

The fourth proportional to 499.89, 689.85 and 278.84 is: 384.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.89 : 689.85 = 278.84 : x
  2. Step 2: Convert to fraction form
    499.89/689.85 = 278.84/x
  3. Step 3: Cross multiply
    499.89x = 689.85 × 278.84
  4. Step 4: Simplify right side
    499.89x = 192,356.38
  5. Step 5: Solve for x
    x = 192,356.38/499.89
  6. Step 6: Final answer
    x = 384.80

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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.