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Finding the Fourth Proportional to 68.96, 103.31 and 56.81

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Solution

The fourth proportional to 68.96, 103.31 and 56.81 is: 85.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.96 : 103.31 = 56.81 : x
  2. Step 2: Convert to fraction form
    68.96/103.31 = 56.81/x
  3. Step 3: Cross multiply
    68.96x = 103.31 × 56.81
  4. Step 4: Simplify right side
    68.96x = 5,868.76
  5. Step 5: Solve for x
    x = 5,868.76/68.96
  6. Step 6: Final answer
    x = 85.10

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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.