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Finding the Fourth Proportional to 420.34, 580.06 and 231.28

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Solution

The fourth proportional to 420.34, 580.06 and 231.28 is: 319.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.34 : 580.06 = 231.28 : x
  2. Step 2: Convert to fraction form
    420.34/580.06 = 231.28/x
  3. Step 3: Cross multiply
    420.34x = 580.06 × 231.28
  4. Step 4: Simplify right side
    420.34x = 134,156.28
  5. Step 5: Solve for x
    x = 134,156.28/420.34
  6. Step 6: Final answer
    x = 319.17

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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.