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Finding the Fourth Proportional to 420.34, 580.13 and 401.88

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Solution

The fourth proportional to 420.34, 580.13 and 401.88 is: 554.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.34 : 580.13 = 401.88 : x
  2. Step 2: Convert to fraction form
    420.34/580.13 = 401.88/x
  3. Step 3: Cross multiply
    420.34x = 580.13 × 401.88
  4. Step 4: Simplify right side
    420.34x = 233,142.64
  5. Step 5: Solve for x
    x = 233,142.64/420.34
  6. Step 6: Final answer
    x = 554.65

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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.