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Finding the Fourth Proportional to 521.76, 781.82 and 423.79

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Solution

The fourth proportional to 521.76, 781.82 and 423.79 is: 635.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.76 : 781.82 = 423.79 : x
  2. Step 2: Convert to fraction form
    521.76/781.82 = 423.79/x
  3. Step 3: Cross multiply
    521.76x = 781.82 × 423.79
  4. Step 4: Simplify right side
    521.76x = 331,322.72
  5. Step 5: Solve for x
    x = 331,322.72/521.76
  6. Step 6: Final answer
    x = 635.01

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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.