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Finding the Fourth Proportional to 386.55, 579.92 and 212.98

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Solution

The fourth proportional to 386.55, 579.92 and 212.98 is: 319.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.55 : 579.92 = 212.98 : x
  2. Step 2: Convert to fraction form
    386.55/579.92 = 212.98/x
  3. Step 3: Cross multiply
    386.55x = 579.92 × 212.98
  4. Step 4: Simplify right side
    386.55x = 123,508.75
  5. Step 5: Solve for x
    x = 123,508.75/386.55
  6. Step 6: Final answer
    x = 319.52

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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.