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Finding the Fourth Proportional to 637.91, 878.13 and 497.78

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Solution

The fourth proportional to 637.91, 878.13 and 497.78 is: 685.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    637.91 : 878.13 = 497.78 : x
  2. Step 2: Convert to fraction form
    637.91/878.13 = 497.78/x
  3. Step 3: Cross multiply
    637.91x = 878.13 × 497.78
  4. Step 4: Simplify right side
    637.91x = 437,111.16
  5. Step 5: Solve for x
    x = 437,111.16/637.91
  6. Step 6: Final answer
    x = 685.23

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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.