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Finding the Fourth Proportional to 520.80, 781.68 and 277.50

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Solution

The fourth proportional to 520.80, 781.68 and 277.50 is: 416.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.80 : 781.68 = 277.50 : x
  2. Step 2: Convert to fraction form
    520.80/781.68 = 277.50/x
  3. Step 3: Cross multiply
    520.80x = 781.68 × 277.50
  4. Step 4: Simplify right side
    520.80x = 216,916.20
  5. Step 5: Solve for x
    x = 216,916.20/520.80
  6. Step 6: Final answer
    x = 416.51

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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.