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Finding the Fourth Proportional to 439.70, 656.91 and 340.20

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Solution

The fourth proportional to 439.70, 656.91 and 340.20 is: 508.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    439.70 : 656.91 = 340.20 : x
  2. Step 2: Convert to fraction form
    439.70/656.91 = 340.20/x
  3. Step 3: Cross multiply
    439.70x = 656.91 × 340.20
  4. Step 4: Simplify right side
    439.70x = 223,480.78
  5. Step 5: Solve for x
    x = 223,480.78/439.70
  6. Step 6: Final answer
    x = 508.26

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.