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Finding the Fourth Proportional to 420.05, 633.30 and 391.82

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Solution

The fourth proportional to 420.05, 633.30 and 391.82 is: 590.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.05 : 633.30 = 391.82 : x
  2. Step 2: Convert to fraction form
    420.05/633.30 = 391.82/x
  3. Step 3: Cross multiply
    420.05x = 633.30 × 391.82
  4. Step 4: Simplify right side
    420.05x = 248,134.48
  5. Step 5: Solve for x
    x = 248,134.48/420.05
  6. Step 6: Final answer
    x = 590.73

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.