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Finding the Fourth Proportional to 521.18, 781.90 and 277.50

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Solution

The fourth proportional to 521.18, 781.90 and 277.50 is: 416.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.18 : 781.90 = 277.50 : x
  2. Step 2: Convert to fraction form
    521.18/781.90 = 277.50/x
  3. Step 3: Cross multiply
    521.18x = 781.90 × 277.50
  4. Step 4: Simplify right side
    521.18x = 216,976.56
  5. Step 5: Solve for x
    x = 216,976.56/521.18
  6. Step 6: Final answer
    x = 416.32

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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.