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Finding the Fourth Proportional to 342.05, 512.26 and 287.78

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Solution

The fourth proportional to 342.05, 512.26 and 287.78 is: 430.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    342.05 : 512.26 = 287.78 : x
  2. Step 2: Convert to fraction form
    342.05/512.26 = 287.78/x
  3. Step 3: Cross multiply
    342.05x = 512.26 × 287.78
  4. Step 4: Simplify right side
    342.05x = 147,414.90
  5. Step 5: Solve for x
    x = 147,414.90/342.05
  6. Step 6: Final answer
    x = 430.98

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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.