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Finding the Fourth Proportional to 865.86, 1,298.79 and 345.83

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Solution

The fourth proportional to 865.86, 1,298.79 and 345.83 is: 518.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    865.86 : 1,298.79 = 345.83 : x
  2. Step 2: Convert to fraction form
    865.86/1,298.79 = 345.83/x
  3. Step 3: Cross multiply
    865.86x = 1,298.79 × 345.83
  4. Step 4: Simplify right side
    865.86x = 449,154.05
  5. Step 5: Solve for x
    x = 449,154.05/865.86
  6. Step 6: Final answer
    x = 518.74

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Double scale
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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.