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Finding the Fourth Proportional to 68.86, 103.90 and 66.36

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Solution

The fourth proportional to 68.86, 103.90 and 66.36 is: 100.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.86 : 103.90 = 66.36 : x
  2. Step 2: Convert to fraction form
    68.86/103.90 = 66.36/x
  3. Step 3: Cross multiply
    68.86x = 103.90 × 66.36
  4. Step 4: Simplify right side
    68.86x = 6,894.80
  5. Step 5: Solve for x
    x = 6,894.80/68.86
  6. Step 6: Final answer
    x = 100.13

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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.