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Finding the Fourth Proportional to 68.53, 102.70 and 42.79

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Solution

The fourth proportional to 68.53, 102.70 and 42.79 is: 64.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.53 : 102.70 = 42.79 : x
  2. Step 2: Convert to fraction form
    68.53/102.70 = 42.79/x
  3. Step 3: Cross multiply
    68.53x = 102.70 × 42.79
  4. Step 4: Simplify right side
    68.53x = 4,394.45
  5. Step 5: Solve for x
    x = 4,394.45/68.53
  6. Step 6: Final answer
    x = 64.12

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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.