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Finding the Fourth Proportional to 84.75, 127.75 and 79.79

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Solution

The fourth proportional to 84.75, 127.75 and 79.79 is: 120.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    84.75 : 127.75 = 79.79 : x
  2. Step 2: Convert to fraction form
    84.75/127.75 = 79.79/x
  3. Step 3: Cross multiply
    84.75x = 127.75 × 79.79
  4. Step 4: Simplify right side
    84.75x = 10,193.01
  5. Step 5: Solve for x
    x = 10,193.01/84.75
  6. Step 6: Final answer
    x = 120.28

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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.