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Finding the Fourth Proportional to 724.40, 999.09 and 663.65

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Solution

The fourth proportional to 724.40, 999.09 and 663.65 is: 915.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    724.40 : 999.09 = 663.65 : x
  2. Step 2: Convert to fraction form
    724.40/999.09 = 663.65/x
  3. Step 3: Cross multiply
    724.40x = 999.09 × 663.65
  4. Step 4: Simplify right side
    724.40x = 663,046.08
  5. Step 5: Solve for x
    x = 663,046.08/724.40
  6. Step 6: Final answer
    x = 915.30

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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.