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Finding the Fourth Proportional to 81.88, 112.95 and 50.78

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Solution

The fourth proportional to 81.88, 112.95 and 50.78 is: 70.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    81.88 : 112.95 = 50.78 : x
  2. Step 2: Convert to fraction form
    81.88/112.95 = 50.78/x
  3. Step 3: Cross multiply
    81.88x = 112.95 × 50.78
  4. Step 4: Simplify right side
    81.88x = 5,735.88
  5. Step 5: Solve for x
    x = 5,735.88/81.88
  6. Step 6: Final answer
    x = 70.05

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.