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Finding the Fourth Proportional to 824.91, 1,137.58 and 638.80

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Solution

The fourth proportional to 824.91, 1,137.58 and 638.80 is: 880.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    824.91 : 1,137.58 = 638.80 : x
  2. Step 2: Convert to fraction form
    824.91/1,137.58 = 638.80/x
  3. Step 3: Cross multiply
    824.91x = 1,137.58 × 638.80
  4. Step 4: Simplify right side
    824.91x = 726,686.10
  5. Step 5: Solve for x
    x = 726,686.10/824.91
  6. Step 6: Final answer
    x = 880.93

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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.