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Finding the Fourth Proportional to 86.44, 130.31 and 80.57

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Solution

The fourth proportional to 86.44, 130.31 and 80.57 is: 121.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.44 : 130.31 = 80.57 : x
  2. Step 2: Convert to fraction form
    86.44/130.31 = 80.57/x
  3. Step 3: Cross multiply
    86.44x = 130.31 × 80.57
  4. Step 4: Simplify right side
    86.44x = 10,498.43
  5. Step 5: Solve for x
    x = 10,498.43/86.44
  6. Step 6: Final answer
    x = 121.45

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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.