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Finding the Fourth Proportional to 131.23, 181.21 and 82.12

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Solution

The fourth proportional to 131.23, 181.21 and 82.12 is: 113.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    131.23 : 181.21 = 82.12 : x
  2. Step 2: Convert to fraction form
    131.23/181.21 = 82.12/x
  3. Step 3: Cross multiply
    131.23x = 181.21 × 82.12
  4. Step 4: Simplify right side
    131.23x = 14,880.97
  5. Step 5: Solve for x
    x = 14,880.97/131.23
  6. Step 6: Final answer
    x = 113.40

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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.