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Finding the Fourth Proportional to 728.50, 1,005.70 and 493.68

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Solution

The fourth proportional to 728.50, 1,005.70 and 493.68 is: 681.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.50 : 1,005.70 = 493.68 : x
  2. Step 2: Convert to fraction form
    728.50/1,005.70 = 493.68/x
  3. Step 3: Cross multiply
    728.50x = 1,005.70 × 493.68
  4. Step 4: Simplify right side
    728.50x = 496,496.52
  5. Step 5: Solve for x
    x = 496,496.52/728.50
  6. Step 6: Final answer
    x = 681.54

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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.