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Finding the Fourth Proportional to 88.22, 120.78 and 85.15

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Solution

The fourth proportional to 88.22, 120.78 and 85.15 is: 116.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    88.22 : 120.78 = 85.15 : x
  2. Step 2: Convert to fraction form
    88.22/120.78 = 85.15/x
  3. Step 3: Cross multiply
    88.22x = 120.78 × 85.15
  4. Step 4: Simplify right side
    88.22x = 10,284.42
  5. Step 5: Solve for x
    x = 10,284.42/88.22
  6. Step 6: Final answer
    x = 116.58

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.