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Finding the Fourth Proportional to 420.65, 580.56 and 252.61

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Solution

The fourth proportional to 420.65, 580.56 and 252.61 is: 348.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.65 : 580.56 = 252.61 : x
  2. Step 2: Convert to fraction form
    420.65/580.56 = 252.61/x
  3. Step 3: Cross multiply
    420.65x = 580.56 × 252.61
  4. Step 4: Simplify right side
    420.65x = 146,655.36
  5. Step 5: Solve for x
    x = 146,655.36/420.65
  6. Step 6: Final answer
    x = 348.64

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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.