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Finding the Fourth Proportional to 82.68, 113.55 and 78.60

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Solution

The fourth proportional to 82.68, 113.55 and 78.60 is: 107.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    82.68 : 113.55 = 78.60 : x
  2. Step 2: Convert to fraction form
    82.68/113.55 = 78.60/x
  3. Step 3: Cross multiply
    82.68x = 113.55 × 78.60
  4. Step 4: Simplify right side
    82.68x = 8,925.03
  5. Step 5: Solve for x
    x = 8,925.03/82.68
  6. Step 6: Final answer
    x = 107.95

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.