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Finding the Fourth Proportional to 521.92, 780.36 and 445.78

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Solution

The fourth proportional to 521.92, 780.36 and 445.78 is: 666.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.92 : 780.36 = 445.78 : x
  2. Step 2: Convert to fraction form
    521.92/780.36 = 445.78/x
  3. Step 3: Cross multiply
    521.92x = 780.36 × 445.78
  4. Step 4: Simplify right side
    521.92x = 347,868.88
  5. Step 5: Solve for x
    x = 347,868.88/521.92
  6. Step 6: Final answer
    x = 666.52

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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.