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Finding the Fourth Proportional to 427.83, 642.47 and 405.91

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Solution

The fourth proportional to 427.83, 642.47 and 405.91 is: 609.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.83 : 642.47 = 405.91 : x
  2. Step 2: Convert to fraction form
    427.83/642.47 = 405.91/x
  3. Step 3: Cross multiply
    427.83x = 642.47 × 405.91
  4. Step 4: Simplify right side
    427.83x = 260,783.77
  5. Step 5: Solve for x
    x = 260,783.77/427.83
  6. Step 6: Final answer
    x = 609.55

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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.