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Finding the Fourth Proportional to 420.60, 579.98 and 308.62

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Solution

The fourth proportional to 420.60, 579.98 and 308.62 is: 425.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.60 : 579.98 = 308.62 : x
  2. Step 2: Convert to fraction form
    420.60/579.98 = 308.62/x
  3. Step 3: Cross multiply
    420.60x = 579.98 × 308.62
  4. Step 4: Simplify right side
    420.60x = 178,988.98
  5. Step 5: Solve for x
    x = 178,988.98/420.60
  6. Step 6: Final answer
    x = 425.56

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.