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Finding the Fourth Proportional to 809.39, 1,214.26 and 347.20

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Solution

The fourth proportional to 809.39, 1,214.26 and 347.20 is: 520.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    809.39 : 1,214.26 = 347.20 : x
  2. Step 2: Convert to fraction form
    809.39/1,214.26 = 347.20/x
  3. Step 3: Cross multiply
    809.39x = 1,214.26 × 347.20
  4. Step 4: Simplify right side
    809.39x = 421,587.17
  5. Step 5: Solve for x
    x = 421,587.17/809.39
  6. Step 6: Final answer
    x = 520.87

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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.