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Finding the Fourth Proportional to 51.79, 78.10 and 51.11

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Solution

The fourth proportional to 51.79, 78.10 and 51.11 is: 77.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    51.79 : 78.10 = 51.11 : x
  2. Step 2: Convert to fraction form
    51.79/78.10 = 51.11/x
  3. Step 3: Cross multiply
    51.79x = 78.10 × 51.11
  4. Step 4: Simplify right side
    51.79x = 3,991.30
  5. Step 5: Solve for x
    x = 3,991.30/51.79
  6. Step 6: Final answer
    x = 77.07

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.