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Finding the Fourth Proportional to 387.11, 534.20 and 212.45

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Solution

The fourth proportional to 387.11, 534.20 and 212.45 is: 293.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.11 : 534.20 = 212.45 : x
  2. Step 2: Convert to fraction form
    387.11/534.20 = 212.45/x
  3. Step 3: Cross multiply
    387.11x = 534.20 × 212.45
  4. Step 4: Simplify right side
    387.11x = 113,490.79
  5. Step 5: Solve for x
    x = 113,490.79/387.11
  6. Step 6: Final answer
    x = 293.17

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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.