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Finding the Fourth Proportional to 420.08, 579.86 and 243.12

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Solution

The fourth proportional to 420.08, 579.86 and 243.12 is: 335.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.08 : 579.86 = 243.12 : x
  2. Step 2: Convert to fraction form
    420.08/579.86 = 243.12/x
  3. Step 3: Cross multiply
    420.08x = 579.86 × 243.12
  4. Step 4: Simplify right side
    420.08x = 140,974.04
  5. Step 5: Solve for x
    x = 140,974.04/420.08
  6. Step 6: Final answer
    x = 335.59

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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.