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Finding the Fourth Proportional to 427.52, 640.32 and 345.28

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Solution

The fourth proportional to 427.52, 640.32 and 345.28 is: 517.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.52 : 640.32 = 345.28 : x
  2. Step 2: Convert to fraction form
    427.52/640.32 = 345.28/x
  3. Step 3: Cross multiply
    427.52x = 640.32 × 345.28
  4. Step 4: Simplify right side
    427.52x = 221,089.69
  5. Step 5: Solve for x
    x = 221,089.69/427.52
  6. Step 6: Final answer
    x = 517.14

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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.