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Finding the Fourth Proportional to 486.78, 730.18 and 121.57

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Solution

The fourth proportional to 486.78, 730.18 and 121.57 is: 182.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.78 : 730.18 = 121.57 : x
  2. Step 2: Convert to fraction form
    486.78/730.18 = 121.57/x
  3. Step 3: Cross multiply
    486.78x = 730.18 × 121.57
  4. Step 4: Simplify right side
    486.78x = 88,768.44
  5. Step 5: Solve for x
    x = 88,768.44/486.78
  6. Step 6: Final answer
    x = 182.36

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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.