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Finding the Fourth Proportional to 427.61, 642.03 and 408.04

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Solution

The fourth proportional to 427.61, 642.03 and 408.04 is: 612.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.61 : 642.03 = 408.04 : x
  2. Step 2: Convert to fraction form
    427.61/642.03 = 408.04/x
  3. Step 3: Cross multiply
    427.61x = 642.03 × 408.04
  4. Step 4: Simplify right side
    427.61x = 261,968.67
  5. Step 5: Solve for x
    x = 261,968.67/427.61
  6. Step 6: Final answer
    x = 612.63

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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.