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Finding the Fourth Proportional to 420.30, 580.02 and 254.47

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Solution

The fourth proportional to 420.30, 580.02 and 254.47 is: 351.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.30 : 580.02 = 254.47 : x
  2. Step 2: Convert to fraction form
    420.30/580.02 = 254.47/x
  3. Step 3: Cross multiply
    420.30x = 580.02 × 254.47
  4. Step 4: Simplify right side
    420.30x = 147,596.42
  5. Step 5: Solve for x
    x = 147,596.42/420.30
  6. Step 6: Final answer
    x = 351.17

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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.