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Finding the Fourth Proportional to 68.80, 95.39 and 65.15

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Solution

The fourth proportional to 68.80, 95.39 and 65.15 is: 90.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.80 : 95.39 = 65.15 : x
  2. Step 2: Convert to fraction form
    68.80/95.39 = 65.15/x
  3. Step 3: Cross multiply
    68.80x = 95.39 × 65.15
  4. Step 4: Simplify right side
    68.80x = 6,214.66
  5. Step 5: Solve for x
    x = 6,214.66/68.80
  6. Step 6: Final answer
    x = 90.33

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.