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Finding the Fourth Proportional to 520.79, 781.38 and 277.20

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Solution

The fourth proportional to 520.79, 781.38 and 277.20 is: 415.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.79 : 781.38 = 277.20 : x
  2. Step 2: Convert to fraction form
    520.79/781.38 = 277.20/x
  3. Step 3: Cross multiply
    520.79x = 781.38 × 277.20
  4. Step 4: Simplify right side
    520.79x = 216,598.54
  5. Step 5: Solve for x
    x = 216,598.54/520.79
  6. Step 6: Final answer
    x = 415.91

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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.