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Finding the Fourth Proportional to 51.28, 76.90 and 50.78

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Solution

The fourth proportional to 51.28, 76.90 and 50.78 is: 76.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    51.28 : 76.90 = 50.78 : x
  2. Step 2: Convert to fraction form
    51.28/76.90 = 50.78/x
  3. Step 3: Cross multiply
    51.28x = 76.90 × 50.78
  4. Step 4: Simplify right side
    51.28x = 3,904.98
  5. Step 5: Solve for x
    x = 3,904.98/51.28
  6. Step 6: Final answer
    x = 76.15

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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.