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Finding the Fourth Proportional to 807.31, 1,211.14 and 320.35

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Solution

The fourth proportional to 807.31, 1,211.14 and 320.35 is: 480.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.31 : 1,211.14 = 320.35 : x
  2. Step 2: Convert to fraction form
    807.31/1,211.14 = 320.35/x
  3. Step 3: Cross multiply
    807.31x = 1,211.14 × 320.35
  4. Step 4: Simplify right side
    807.31x = 387,984.87
  5. Step 5: Solve for x
    x = 387,984.87/807.31
  6. Step 6: Final answer
    x = 480.59

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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.