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Finding the Fourth Proportional to 420.17, 579.15 and 272.55

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Solution

The fourth proportional to 420.17, 579.15 and 272.55 is: 375.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.17 : 579.15 = 272.55 : x
  2. Step 2: Convert to fraction form
    420.17/579.15 = 272.55/x
  3. Step 3: Cross multiply
    420.17x = 579.15 × 272.55
  4. Step 4: Simplify right side
    420.17x = 157,847.33
  5. Step 5: Solve for x
    x = 157,847.33/420.17
  6. Step 6: Final answer
    x = 375.68

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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.