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Finding the Fourth Proportional to 82.74, 114.71 and 78.78

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Solution

The fourth proportional to 82.74, 114.71 and 78.78 is: 109.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    82.74 : 114.71 = 78.78 : x
  2. Step 2: Convert to fraction form
    82.74/114.71 = 78.78/x
  3. Step 3: Cross multiply
    82.74x = 114.71 × 78.78
  4. Step 4: Simplify right side
    82.74x = 9,037.05
  5. Step 5: Solve for x
    x = 9,037.05/82.74
  6. Step 6: Final answer
    x = 109.22

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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.