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Finding the Fourth Proportional to 158.31, 218.57 and 100.17

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Solution

The fourth proportional to 158.31, 218.57 and 100.17 is: 138.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    158.31 : 218.57 = 100.17 : x
  2. Step 2: Convert to fraction form
    158.31/218.57 = 100.17/x
  3. Step 3: Cross multiply
    158.31x = 218.57 × 100.17
  4. Step 4: Simplify right side
    158.31x = 21,893.66
  5. Step 5: Solve for x
    x = 21,893.66/158.31
  6. Step 6: Final answer
    x = 138.30

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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.