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Finding the Fourth Proportional to 427.05, 639.38 and 340.52

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Solution

The fourth proportional to 427.05, 639.38 and 340.52 is: 509.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.05 : 639.38 = 340.52 : x
  2. Step 2: Convert to fraction form
    427.05/639.38 = 340.52/x
  3. Step 3: Cross multiply
    427.05x = 639.38 × 340.52
  4. Step 4: Simplify right side
    427.05x = 217,716.78
  5. Step 5: Solve for x
    x = 217,716.78/427.05
  6. Step 6: Final answer
    x = 509.82

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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.