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Finding the Fourth Proportional to 45.53, 68.31 and 19.87

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Solution

The fourth proportional to 45.53, 68.31 and 19.87 is: 29.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    45.53 : 68.31 = 19.87 : x
  2. Step 2: Convert to fraction form
    45.53/68.31 = 19.87/x
  3. Step 3: Cross multiply
    45.53x = 68.31 × 19.87
  4. Step 4: Simplify right side
    45.53x = 1,357.15
  5. Step 5: Solve for x
    x = 1,357.15/45.53
  6. Step 6: Final answer
    x = 29.81

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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.