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Finding the Fourth Proportional to 486.78, 730.20 and 198.30

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Solution

The fourth proportional to 486.78, 730.20 and 198.30 is: 297.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.78 : 730.20 = 198.30 : x
  2. Step 2: Convert to fraction form
    486.78/730.20 = 198.30/x
  3. Step 3: Cross multiply
    486.78x = 730.20 × 198.30
  4. Step 4: Simplify right side
    486.78x = 144,798.66
  5. Step 5: Solve for x
    x = 144,798.66/486.78
  6. Step 6: Final answer
    x = 297.46

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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.