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Finding the Fourth Proportional to 521.78, 782.61 and 156.80

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Solution

The fourth proportional to 521.78, 782.61 and 156.80 is: 235.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.78 : 782.61 = 156.80 : x
  2. Step 2: Convert to fraction form
    521.78/782.61 = 156.80/x
  3. Step 3: Cross multiply
    521.78x = 782.61 × 156.80
  4. Step 4: Simplify right side
    521.78x = 122,709.33
  5. Step 5: Solve for x
    x = 122,709.33/521.78
  6. Step 6: Final answer
    x = 235.18

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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.