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Finding the Fourth Proportional to 521.68, 782.31 and 278.17

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Solution

The fourth proportional to 521.68, 782.31 and 278.17 is: 417.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.68 : 782.31 = 278.17 : x
  2. Step 2: Convert to fraction form
    521.68/782.31 = 278.17/x
  3. Step 3: Cross multiply
    521.68x = 782.31 × 278.17
  4. Step 4: Simplify right side
    521.68x = 217,615.17
  5. Step 5: Solve for x
    x = 217,615.17/521.68
  6. Step 6: Final answer
    x = 417.14

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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.