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Finding the Fourth Proportional to 807.96, 1,212 and 287.90

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Solution

The fourth proportional to 807.96, 1,212 and 287.90 is: 431.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.96 : 1,212 = 287.90 : x
  2. Step 2: Convert to fraction form
    807.96/1,212 = 287.90/x
  3. Step 3: Cross multiply
    807.96x = 1,212 × 287.90
  4. Step 4: Simplify right side
    807.96x = 348,934.80
  5. Step 5: Solve for x
    x = 348,934.80/807.96
  6. Step 6: Final answer
    x = 431.87

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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.