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Finding the Fourth Proportional to 158.21, 237.21 and 81.15

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Solution

The fourth proportional to 158.21, 237.21 and 81.15 is: 121.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    158.21 : 237.21 = 81.15 : x
  2. Step 2: Convert to fraction form
    158.21/237.21 = 81.15/x
  3. Step 3: Cross multiply
    158.21x = 237.21 × 81.15
  4. Step 4: Simplify right side
    158.21x = 19,249.59
  5. Step 5: Solve for x
    x = 19,249.59/158.21
  6. Step 6: Final answer
    x = 121.67

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.