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Finding the Fourth Proportional to 685.17, 1,027.50 and 539.21

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Solution

The fourth proportional to 685.17, 1,027.50 and 539.21 is: 808.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.17 : 1,027.50 = 539.21 : x
  2. Step 2: Convert to fraction form
    685.17/1,027.50 = 539.21/x
  3. Step 3: Cross multiply
    685.17x = 1,027.50 × 539.21
  4. Step 4: Simplify right side
    685.17x = 554,038.28
  5. Step 5: Solve for x
    x = 554,038.28/685.17
  6. Step 6: Final answer
    x = 808.61

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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.