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Finding the Fourth Proportional to 420.86, 581.04 and 271.55

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Solution

The fourth proportional to 420.86, 581.04 and 271.55 is: 374.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.86 : 581.04 = 271.55 : x
  2. Step 2: Convert to fraction form
    420.86/581.04 = 271.55/x
  3. Step 3: Cross multiply
    420.86x = 581.04 × 271.55
  4. Step 4: Simplify right side
    420.86x = 157,781.41
  5. Step 5: Solve for x
    x = 157,781.41/420.86
  6. Step 6: Final answer
    x = 374.90

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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.