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Finding the Fourth Proportional to 655.20, 976.86 and 638.10

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Solution

The fourth proportional to 655.20, 976.86 and 638.10 is: 951.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    655.20 : 976.86 = 638.10 : x
  2. Step 2: Convert to fraction form
    655.20/976.86 = 638.10/x
  3. Step 3: Cross multiply
    655.20x = 976.86 × 638.10
  4. Step 4: Simplify right side
    655.20x = 623,334.37
  5. Step 5: Solve for x
    x = 623,334.37/655.20
  6. Step 6: Final answer
    x = 951.37

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.