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Finding the Fourth Proportional to 865.72, 1,298.89 and 540.71

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Solution

The fourth proportional to 865.72, 1,298.89 and 540.71 is: 811.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    865.72 : 1,298.89 = 540.71 : x
  2. Step 2: Convert to fraction form
    865.72/1,298.89 = 540.71/x
  3. Step 3: Cross multiply
    865.72x = 1,298.89 × 540.71
  4. Step 4: Simplify right side
    865.72x = 702,322.81
  5. Step 5: Solve for x
    x = 702,322.81/865.72
  6. Step 6: Final answer
    x = 811.26

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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.