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Finding the Fourth Proportional to 521.48, 782.18 and 213.28

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Solution

The fourth proportional to 521.48, 782.18 and 213.28 is: 319.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.48 : 782.18 = 213.28 : x
  2. Step 2: Convert to fraction form
    521.48/782.18 = 213.28/x
  3. Step 3: Cross multiply
    521.48x = 782.18 × 213.28
  4. Step 4: Simplify right side
    521.48x = 166,823.35
  5. Step 5: Solve for x
    x = 166,823.35/521.48
  6. Step 6: Final answer
    x = 319.90

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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.