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Finding the Fourth Proportional to 521.89, 782.38 and 278.59

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Solution

The fourth proportional to 521.89, 782.38 and 278.59 is: 417.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.89 : 782.38 = 278.59 : x
  2. Step 2: Convert to fraction form
    521.89/782.38 = 278.59/x
  3. Step 3: Cross multiply
    521.89x = 782.38 × 278.59
  4. Step 4: Simplify right side
    521.89x = 217,963.24
  5. Step 5: Solve for x
    x = 217,963.24/521.89
  6. Step 6: Final answer
    x = 417.64

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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.