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Finding the Fourth Proportional to 420.47, 580.30 and 254.69

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Solution

The fourth proportional to 420.47, 580.30 and 254.69 is: 351.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.47 : 580.30 = 254.69 : x
  2. Step 2: Convert to fraction form
    420.47/580.30 = 254.69/x
  3. Step 3: Cross multiply
    420.47x = 580.30 × 254.69
  4. Step 4: Simplify right side
    420.47x = 147,795.65
  5. Step 5: Solve for x
    x = 147,795.65/420.47
  6. Step 6: Final answer
    x = 351.50

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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.