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Finding the Fourth Proportional to 68.88, 102.72 and 67.80

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Solution

The fourth proportional to 68.88, 102.72 and 67.80 is: 101.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.88 : 102.72 = 67.80 : x
  2. Step 2: Convert to fraction form
    68.88/102.72 = 67.80/x
  3. Step 3: Cross multiply
    68.88x = 102.72 × 67.80
  4. Step 4: Simplify right side
    68.88x = 6,964.42
  5. Step 5: Solve for x
    x = 6,964.42/68.88
  6. Step 6: Final answer
    x = 101.11

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.