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Finding the Fourth Proportional to 68.70, 94.78 and 39.58

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Solution

The fourth proportional to 68.70, 94.78 and 39.58 is: 54.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.70 : 94.78 = 39.58 : x
  2. Step 2: Convert to fraction form
    68.70/94.78 = 39.58/x
  3. Step 3: Cross multiply
    68.70x = 94.78 × 39.58
  4. Step 4: Simplify right side
    68.70x = 3,751.39
  5. Step 5: Solve for x
    x = 3,751.39/68.70
  6. Step 6: Final answer
    x = 54.61

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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.