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Finding the Fourth Proportional to 136.29, 188.12 and 87.21

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Solution

The fourth proportional to 136.29, 188.12 and 87.21 is: 120.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    136.29 : 188.12 = 87.21 : x
  2. Step 2: Convert to fraction form
    136.29/188.12 = 87.21/x
  3. Step 3: Cross multiply
    136.29x = 188.12 × 87.21
  4. Step 4: Simplify right side
    136.29x = 16,405.51
  5. Step 5: Solve for x
    x = 16,405.51/136.29
  6. Step 6: Final answer
    x = 120.37

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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.