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Finding the Fourth Proportional to 89.60, 135.20 and 86.60

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Solution

The fourth proportional to 89.60, 135.20 and 86.60 is: 130.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    89.60 : 135.20 = 86.60 : x
  2. Step 2: Convert to fraction form
    89.60/135.20 = 86.60/x
  3. Step 3: Cross multiply
    89.60x = 135.20 × 86.60
  4. Step 4: Simplify right side
    89.60x = 11,708.32
  5. Step 5: Solve for x
    x = 11,708.32/89.60
  6. Step 6: Final answer
    x = 130.67

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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.