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Finding the Fourth Proportional to 78.88, 118.88 and 76.48

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Solution

The fourth proportional to 78.88, 118.88 and 76.48 is: 115.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.88 : 118.88 = 76.48 : x
  2. Step 2: Convert to fraction form
    78.88/118.88 = 76.48/x
  3. Step 3: Cross multiply
    78.88x = 118.88 × 76.48
  4. Step 4: Simplify right side
    78.88x = 9,091.94
  5. Step 5: Solve for x
    x = 9,091.94/78.88
  6. Step 6: Final answer
    x = 115.26

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.