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Finding the Fourth Proportional to 387.11, 534.12 and 221.33

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Solution

The fourth proportional to 387.11, 534.12 and 221.33 is: 305.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.11 : 534.12 = 221.33 : x
  2. Step 2: Convert to fraction form
    387.11/534.12 = 221.33/x
  3. Step 3: Cross multiply
    387.11x = 534.12 × 221.33
  4. Step 4: Simplify right side
    387.11x = 118,216.78
  5. Step 5: Solve for x
    x = 118,216.78/387.11
  6. Step 6: Final answer
    x = 305.38

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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.