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Finding the Fourth Proportional to 865.89, 1,298.84 and 379.28

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Solution

The fourth proportional to 865.89, 1,298.84 and 379.28 is: 568.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    865.89 : 1,298.84 = 379.28 : x
  2. Step 2: Convert to fraction form
    865.89/1,298.84 = 379.28/x
  3. Step 3: Cross multiply
    865.89x = 1,298.84 × 379.28
  4. Step 4: Simplify right side
    865.89x = 492,615.64
  5. Step 5: Solve for x
    x = 492,615.64/865.89
  6. Step 6: Final answer
    x = 568.91

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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.