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Finding the Fourth Proportional to 29.91, 41.30 and 28.90

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Solution

The fourth proportional to 29.91, 41.30 and 28.90 is: 39.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    29.91 : 41.30 = 28.90 : x
  2. Step 2: Convert to fraction form
    29.91/41.30 = 28.90/x
  3. Step 3: Cross multiply
    29.91x = 41.30 × 28.90
  4. Step 4: Simplify right side
    29.91x = 1,193.57
  5. Step 5: Solve for x
    x = 1,193.57/29.91
  6. Step 6: Final answer
    x = 39.91

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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.