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Finding the Fourth Proportional to 807.48, 1,210.91 and 287.39

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Solution

The fourth proportional to 807.48, 1,210.91 and 287.39 is: 430.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.48 : 1,210.91 = 287.39 : x
  2. Step 2: Convert to fraction form
    807.48/1,210.91 = 287.39/x
  3. Step 3: Cross multiply
    807.48x = 1,210.91 × 287.39
  4. Step 4: Simplify right side
    807.48x = 347,997.61
  5. Step 5: Solve for x
    x = 347,997.61/807.48
  6. Step 6: Final answer
    x = 430.97

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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.