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Finding the Fourth Proportional to 387.43, 579.84 and 211.49

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Solution

The fourth proportional to 387.43, 579.84 and 211.49 is: 316.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.43 : 579.84 = 211.49 : x
  2. Step 2: Convert to fraction form
    387.43/579.84 = 211.49/x
  3. Step 3: Cross multiply
    387.43x = 579.84 × 211.49
  4. Step 4: Simplify right side
    387.43x = 122,630.36
  5. Step 5: Solve for x
    x = 122,630.36/387.43
  6. Step 6: Final answer
    x = 316.52

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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.