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Finding the Fourth Proportional to 521.22, 781.20 and 277.40

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Solution

The fourth proportional to 521.22, 781.20 and 277.40 is: 415.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.22 : 781.20 = 277.40 : x
  2. Step 2: Convert to fraction form
    521.22/781.20 = 277.40/x
  3. Step 3: Cross multiply
    521.22x = 781.20 × 277.40
  4. Step 4: Simplify right side
    521.22x = 216,704.88
  5. Step 5: Solve for x
    x = 216,704.88/521.22
  6. Step 6: Final answer
    x = 415.76

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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.