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Finding the Fourth Proportional to 427.30, 639.77 and 280.62

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Solution

The fourth proportional to 427.30, 639.77 and 280.62 is: 420.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.30 : 639.77 = 280.62 : x
  2. Step 2: Convert to fraction form
    427.30/639.77 = 280.62/x
  3. Step 3: Cross multiply
    427.30x = 639.77 × 280.62
  4. Step 4: Simplify right side
    427.30x = 179,530.85
  5. Step 5: Solve for x
    x = 179,530.85/427.30
  6. Step 6: Final answer
    x = 420.15

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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.