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Finding the Fourth Proportional to 778.75, 1,167.80 and 388.61

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Solution

The fourth proportional to 778.75, 1,167.80 and 388.61 is: 582.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    778.75 : 1,167.80 = 388.61 : x
  2. Step 2: Convert to fraction form
    778.75/1,167.80 = 388.61/x
  3. Step 3: Cross multiply
    778.75x = 1,167.80 × 388.61
  4. Step 4: Simplify right side
    778.75x = 453,815.36
  5. Step 5: Solve for x
    x = 453,815.36/778.75
  6. Step 6: Final answer
    x = 582.75

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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.