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Finding the Fourth Proportional to 155.38, 214.31 and 100.09

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Solution

The fourth proportional to 155.38, 214.31 and 100.09 is: 138.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    155.38 : 214.31 = 100.09 : x
  2. Step 2: Convert to fraction form
    155.38/214.31 = 100.09/x
  3. Step 3: Cross multiply
    155.38x = 214.31 × 100.09
  4. Step 4: Simplify right side
    155.38x = 21,448.72
  5. Step 5: Solve for x
    x = 21,448.72/155.38
  6. Step 6: Final answer
    x = 138.04

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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.