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Finding the Fourth Proportional to 865.56, 1,298.26 and 280.51

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Solution

The fourth proportional to 865.56, 1,298.26 and 280.51 is: 420.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    865.56 : 1,298.26 = 280.51 : x
  2. Step 2: Convert to fraction form
    865.56/1,298.26 = 280.51/x
  3. Step 3: Cross multiply
    865.56x = 1,298.26 × 280.51
  4. Step 4: Simplify right side
    865.56x = 364,174.91
  5. Step 5: Solve for x
    x = 364,174.91/865.56
  6. Step 6: Final answer
    x = 420.74

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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.