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Finding the Fourth Proportional to 420.38, 630.73 and 379.66

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Solution

The fourth proportional to 420.38, 630.73 and 379.66 is: 569.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.38 : 630.73 = 379.66 : x
  2. Step 2: Convert to fraction form
    420.38/630.73 = 379.66/x
  3. Step 3: Cross multiply
    420.38x = 630.73 × 379.66
  4. Step 4: Simplify right side
    420.38x = 239,462.95
  5. Step 5: Solve for x
    x = 239,462.95/420.38
  6. Step 6: Final answer
    x = 569.63

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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.