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Finding the Fourth Proportional to 664.80, 997.20 and 637.80

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Solution

The fourth proportional to 664.80, 997.20 and 637.80 is: 956.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    664.80 : 997.20 = 637.80 : x
  2. Step 2: Convert to fraction form
    664.80/997.20 = 637.80/x
  3. Step 3: Cross multiply
    664.80x = 997.20 × 637.80
  4. Step 4: Simplify right side
    664.80x = 636,014.16
  5. Step 5: Solve for x
    x = 636,014.16/664.80
  6. Step 6: Final answer
    x = 956.70

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.