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Finding the Fourth Proportional to 387.81, 535.19 and 213.17

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Solution

The fourth proportional to 387.81, 535.19 and 213.17 is: 294.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.81 : 535.19 = 213.17 : x
  2. Step 2: Convert to fraction form
    387.81/535.19 = 213.17/x
  3. Step 3: Cross multiply
    387.81x = 535.19 × 213.17
  4. Step 4: Simplify right side
    387.81x = 114,086.45
  5. Step 5: Solve for x
    x = 114,086.45/387.81
  6. Step 6: Final answer
    x = 294.18

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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.