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Finding the Fourth Proportional to 420.27, 579.95 and 243.21

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Solution

The fourth proportional to 420.27, 579.95 and 243.21 is: 335.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.27 : 579.95 = 243.21 : x
  2. Step 2: Convert to fraction form
    420.27/579.95 = 243.21/x
  3. Step 3: Cross multiply
    420.27x = 579.95 × 243.21
  4. Step 4: Simplify right side
    420.27x = 141,046.74
  5. Step 5: Solve for x
    x = 141,046.74/420.27
  6. Step 6: Final answer
    x = 335.61

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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.