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Finding the Fourth Proportional to 387.70, 580.33 and 220.70

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Solution

The fourth proportional to 387.70, 580.33 and 220.70 is: 330.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.70 : 580.33 = 220.70 : x
  2. Step 2: Convert to fraction form
    387.70/580.33 = 220.70/x
  3. Step 3: Cross multiply
    387.70x = 580.33 × 220.70
  4. Step 4: Simplify right side
    387.70x = 128,080.28
  5. Step 5: Solve for x
    x = 128,080.28/387.70
  6. Step 6: Final answer
    x = 330.36

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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.