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Finding the Fourth Proportional to 68.10, 94.05 and 51.78

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Solution

The fourth proportional to 68.10, 94.05 and 51.78 is: 71.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.10 : 94.05 = 51.78 : x
  2. Step 2: Convert to fraction form
    68.10/94.05 = 51.78/x
  3. Step 3: Cross multiply
    68.10x = 94.05 × 51.78
  4. Step 4: Simplify right side
    68.10x = 4,869.91
  5. Step 5: Solve for x
    x = 4,869.91/68.10
  6. Step 6: Final answer
    x = 71.51

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.