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Finding the Fourth Proportional to 663.61, 993.39 and 653.89

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Solution

The fourth proportional to 663.61, 993.39 and 653.89 is: 978.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.61 : 993.39 = 653.89 : x
  2. Step 2: Convert to fraction form
    663.61/993.39 = 653.89/x
  3. Step 3: Cross multiply
    663.61x = 993.39 × 653.89
  4. Step 4: Simplify right side
    663.61x = 649,567.79
  5. Step 5: Solve for x
    x = 649,567.79/663.61
  6. Step 6: Final answer
    x = 978.84

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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.