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Finding the Fourth Proportional to 155.39, 214.41 and 86.39

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Solution

The fourth proportional to 155.39, 214.41 and 86.39 is: 119.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    155.39 : 214.41 = 86.39 : x
  2. Step 2: Convert to fraction form
    155.39/214.41 = 86.39/x
  3. Step 3: Cross multiply
    155.39x = 214.41 × 86.39
  4. Step 4: Simplify right side
    155.39x = 18,522.88
  5. Step 5: Solve for x
    x = 18,522.88/155.39
  6. Step 6: Final answer
    x = 119.20

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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.