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Finding the Fourth Proportional to 521.05, 781.58 and 212.84

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Solution

The fourth proportional to 521.05, 781.58 and 212.84 is: 319.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.05 : 781.58 = 212.84 : x
  2. Step 2: Convert to fraction form
    521.05/781.58 = 212.84/x
  3. Step 3: Cross multiply
    521.05x = 781.58 × 212.84
  4. Step 4: Simplify right side
    521.05x = 166,351.49
  5. Step 5: Solve for x
    x = 166,351.49/521.05
  6. Step 6: Final answer
    x = 319.26

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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.