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Finding the Fourth Proportional to 51.20, 76.81 and 15.13

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Solution

The fourth proportional to 51.20, 76.81 and 15.13 is: 22.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    51.20 : 76.81 = 15.13 : x
  2. Step 2: Convert to fraction form
    51.20/76.81 = 15.13/x
  3. Step 3: Cross multiply
    51.20x = 76.81 × 15.13
  4. Step 4: Simplify right side
    51.20x = 1,162.14
  5. Step 5: Solve for x
    x = 1,162.14/51.20
  6. Step 6: Final answer
    x = 22.70

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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.