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Finding the Fourth Proportional to 486.70, 730.12 and 212.80

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Solution

The fourth proportional to 486.70, 730.12 and 212.80 is: 319.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.70 : 730.12 = 212.80 : x
  2. Step 2: Convert to fraction form
    486.70/730.12 = 212.80/x
  3. Step 3: Cross multiply
    486.70x = 730.12 × 212.80
  4. Step 4: Simplify right side
    486.70x = 155,369.54
  5. Step 5: Solve for x
    x = 155,369.54/486.70
  6. Step 6: Final answer
    x = 319.23

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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.