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Finding the Fourth Proportional to 521.28, 781.76 and 196.80

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Solution

The fourth proportional to 521.28, 781.76 and 196.80 is: 295.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.28 : 781.76 = 196.80 : x
  2. Step 2: Convert to fraction form
    521.28/781.76 = 196.80/x
  3. Step 3: Cross multiply
    521.28x = 781.76 × 196.80
  4. Step 4: Simplify right side
    521.28x = 153,850.37
  5. Step 5: Solve for x
    x = 153,850.37/521.28
  6. Step 6: Final answer
    x = 295.14

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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.