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Finding the Fourth Proportional to 508.30, 760.61 and 420.82

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Solution

The fourth proportional to 508.30, 760.61 and 420.82 is: 629.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    508.30 : 760.61 = 420.82 : x
  2. Step 2: Convert to fraction form
    508.30/760.61 = 420.82/x
  3. Step 3: Cross multiply
    508.30x = 760.61 × 420.82
  4. Step 4: Simplify right side
    508.30x = 320,079.05
  5. Step 5: Solve for x
    x = 320,079.05/508.30
  6. Step 6: Final answer
    x = 629.71

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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.