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Finding the Fourth Proportional to 425.68, 639.04 and 280.08

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Solution

The fourth proportional to 425.68, 639.04 and 280.08 is: 420.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    425.68 : 639.04 = 280.08 : x
  2. Step 2: Convert to fraction form
    425.68/639.04 = 280.08/x
  3. Step 3: Cross multiply
    425.68x = 639.04 × 280.08
  4. Step 4: Simplify right side
    425.68x = 178,982.32
  5. Step 5: Solve for x
    x = 178,982.32/425.68
  6. Step 6: Final answer
    x = 420.46

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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.