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Finding the Fourth Proportional to 23.20, 31.92 and 21.60

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Solution

The fourth proportional to 23.20, 31.92 and 21.60 is: 29.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    23.20 : 31.92 = 21.60 : x
  2. Step 2: Convert to fraction form
    23.20/31.92 = 21.60/x
  3. Step 3: Cross multiply
    23.20x = 31.92 × 21.60
  4. Step 4: Simplify right side
    23.20x = 689.47
  5. Step 5: Solve for x
    x = 689.47/23.20
  6. Step 6: Final answer
    x = 29.72

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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.