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Finding the Fourth Proportional to 68.50, 102.80 and 25.75

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Solution

The fourth proportional to 68.50, 102.80 and 25.75 is: 38.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.50 : 102.80 = 25.75 : x
  2. Step 2: Convert to fraction form
    68.50/102.80 = 25.75/x
  3. Step 3: Cross multiply
    68.50x = 102.80 × 25.75
  4. Step 4: Simplify right side
    68.50x = 2,647.10
  5. Step 5: Solve for x
    x = 2,647.10/68.50
  6. Step 6: Final answer
    x = 38.64

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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.