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Finding the Fourth Proportional to 427.24, 639.81 and 339.94

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Solution

The fourth proportional to 427.24, 639.81 and 339.94 is: 509.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.24 : 639.81 = 339.94 : x
  2. Step 2: Convert to fraction form
    427.24/639.81 = 339.94/x
  3. Step 3: Cross multiply
    427.24x = 639.81 × 339.94
  4. Step 4: Simplify right side
    427.24x = 217,497.01
  5. Step 5: Solve for x
    x = 217,497.01/427.24
  6. Step 6: Final answer
    x = 509.07

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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.