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Finding the Fourth Proportional to 521.34, 782.09 and 213.18

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Solution

The fourth proportional to 521.34, 782.09 and 213.18 is: 319.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.34 : 782.09 = 213.18 : x
  2. Step 2: Convert to fraction form
    521.34/782.09 = 213.18/x
  3. Step 3: Cross multiply
    521.34x = 782.09 × 213.18
  4. Step 4: Simplify right side
    521.34x = 166,724.88
  5. Step 5: Solve for x
    x = 166,724.88/521.34
  6. Step 6: Final answer
    x = 319.80

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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.