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Finding the Fourth Proportional to 723.40, 1,085.82 and 398.92

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Solution

The fourth proportional to 723.40, 1,085.82 and 398.92 is: 598.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    723.40 : 1,085.82 = 398.92 : x
  2. Step 2: Convert to fraction form
    723.40/1,085.82 = 398.92/x
  3. Step 3: Cross multiply
    723.40x = 1,085.82 × 398.92
  4. Step 4: Simplify right side
    723.40x = 433,155.31
  5. Step 5: Solve for x
    x = 433,155.31/723.40
  6. Step 6: Final answer
    x = 598.78

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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.