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Finding the Fourth Proportional to 45.29, 67.86 and 20.88

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Solution

The fourth proportional to 45.29, 67.86 and 20.88 is: 31.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    45.29 : 67.86 = 20.88 : x
  2. Step 2: Convert to fraction form
    45.29/67.86 = 20.88/x
  3. Step 3: Cross multiply
    45.29x = 67.86 × 20.88
  4. Step 4: Simplify right side
    45.29x = 1,416.53
  5. Step 5: Solve for x
    x = 1,416.53/45.29
  6. Step 6: Final answer
    x = 31.28

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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.