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Finding the Fourth Proportional to 68.12, 102.70 and 57.56

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Solution

The fourth proportional to 68.12, 102.70 and 57.56 is: 86.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.12 : 102.70 = 57.56 : x
  2. Step 2: Convert to fraction form
    68.12/102.70 = 57.56/x
  3. Step 3: Cross multiply
    68.12x = 102.70 × 57.56
  4. Step 4: Simplify right side
    68.12x = 5,911.41
  5. Step 5: Solve for x
    x = 5,911.41/68.12
  6. Step 6: Final answer
    x = 86.78

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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.