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Finding the Fourth Proportional to 501.23, 691.76 and 280.20

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Solution

The fourth proportional to 501.23, 691.76 and 280.20 is: 386.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    501.23 : 691.76 = 280.20 : x
  2. Step 2: Convert to fraction form
    501.23/691.76 = 280.20/x
  3. Step 3: Cross multiply
    501.23x = 691.76 × 280.20
  4. Step 4: Simplify right side
    501.23x = 193,831.85
  5. Step 5: Solve for x
    x = 193,831.85/501.23
  6. Step 6: Final answer
    x = 386.71

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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.