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Finding the Fourth Proportional to 807.35, 1,211.20 and 287.38

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Solution

The fourth proportional to 807.35, 1,211.20 and 287.38 is: 431.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.35 : 1,211.20 = 287.38 : x
  2. Step 2: Convert to fraction form
    807.35/1,211.20 = 287.38/x
  3. Step 3: Cross multiply
    807.35x = 1,211.20 × 287.38
  4. Step 4: Simplify right side
    807.35x = 348,074.66
  5. Step 5: Solve for x
    x = 348,074.66/807.35
  6. Step 6: Final answer
    x = 431.13

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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.