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Finding the Fourth Proportional to 521.78, 782.48 and 213.47

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Solution

The fourth proportional to 521.78, 782.48 and 213.47 is: 320.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.78 : 782.48 = 213.47 : x
  2. Step 2: Convert to fraction form
    521.78/782.48 = 213.47/x
  3. Step 3: Cross multiply
    521.78x = 782.48 × 213.47
  4. Step 4: Simplify right side
    521.78x = 167,031.03
  5. Step 5: Solve for x
    x = 167,031.03/521.78
  6. Step 6: Final answer
    x = 320.12

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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.