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Finding the Fourth Proportional to 187.30, 258.15 and 138.30

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Solution

The fourth proportional to 187.30, 258.15 and 138.30 is: 190.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    187.30 : 258.15 = 138.30 : x
  2. Step 2: Convert to fraction form
    187.30/258.15 = 138.30/x
  3. Step 3: Cross multiply
    187.30x = 258.15 × 138.30
  4. Step 4: Simplify right side
    187.30x = 35,702.15
  5. Step 5: Solve for x
    x = 35,702.15/187.30
  6. Step 6: Final answer
    x = 190.61

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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.