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Finding the Fourth Proportional to 865.41, 1,298.13 and 378.09

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Solution

The fourth proportional to 865.41, 1,298.13 and 378.09 is: 567.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    865.41 : 1,298.13 = 378.09 : x
  2. Step 2: Convert to fraction form
    865.41/1,298.13 = 378.09/x
  3. Step 3: Cross multiply
    865.41x = 1,298.13 × 378.09
  4. Step 4: Simplify right side
    865.41x = 490,809.97
  5. Step 5: Solve for x
    x = 490,809.97/865.41
  6. Step 6: Final answer
    x = 567.14

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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.