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Finding the Fourth Proportional to 665.80, 920.12 and 500.56

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Solution

The fourth proportional to 665.80, 920.12 and 500.56 is: 691.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.80 : 920.12 = 500.56 : x
  2. Step 2: Convert to fraction form
    665.80/920.12 = 500.56/x
  3. Step 3: Cross multiply
    665.80x = 920.12 × 500.56
  4. Step 4: Simplify right side
    665.80x = 460,575.27
  5. Step 5: Solve for x
    x = 460,575.27/665.80
  6. Step 6: Final answer
    x = 691.76

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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.