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Finding the Fourth Proportional to 638.78, 880.80 and 498.92

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Solution

The fourth proportional to 638.78, 880.80 and 498.92 is: 687.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.78 : 880.80 = 498.92 : x
  2. Step 2: Convert to fraction form
    638.78/880.80 = 498.92/x
  3. Step 3: Cross multiply
    638.78x = 880.80 × 498.92
  4. Step 4: Simplify right side
    638.78x = 439,448.74
  5. Step 5: Solve for x
    x = 439,448.74/638.78
  6. Step 6: Final answer
    x = 687.95

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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.