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Finding the Fourth Proportional to 285.91, 428.90 and 123.61

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Solution

The fourth proportional to 285.91, 428.90 and 123.61 is: 185.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.91 : 428.90 = 123.61 : x
  2. Step 2: Convert to fraction form
    285.91/428.90 = 123.61/x
  3. Step 3: Cross multiply
    285.91x = 428.90 × 123.61
  4. Step 4: Simplify right side
    285.91x = 53,015.44
  5. Step 5: Solve for x
    x = 53,015.44/285.91
  6. Step 6: Final answer
    x = 185.43

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.