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Finding the Fourth Proportional to 23.14, 31.86 and 21.78

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Solution

The fourth proportional to 23.14, 31.86 and 21.78 is: 29.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    23.14 : 31.86 = 21.78 : x
  2. Step 2: Convert to fraction form
    23.14/31.86 = 21.78/x
  3. Step 3: Cross multiply
    23.14x = 31.86 × 21.78
  4. Step 4: Simplify right side
    23.14x = 693.91
  5. Step 5: Solve for x
    x = 693.91/23.14
  6. Step 6: Final answer
    x = 29.99

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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.