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Finding the Fourth Proportional to 88.26, 121.79 and 85.30

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Solution

The fourth proportional to 88.26, 121.79 and 85.30 is: 117.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    88.26 : 121.79 = 85.30 : x
  2. Step 2: Convert to fraction form
    88.26/121.79 = 85.30/x
  3. Step 3: Cross multiply
    88.26x = 121.79 × 85.30
  4. Step 4: Simplify right side
    88.26x = 10,388.69
  5. Step 5: Solve for x
    x = 10,388.69/88.26
  6. Step 6: Final answer
    x = 117.71

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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.