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Finding the Fourth Proportional to 121.41, 182.12 and 99.72

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Solution

The fourth proportional to 121.41, 182.12 and 99.72 is: 149.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    121.41 : 182.12 = 99.72 : x
  2. Step 2: Convert to fraction form
    121.41/182.12 = 99.72/x
  3. Step 3: Cross multiply
    121.41x = 182.12 × 99.72
  4. Step 4: Simplify right side
    121.41x = 18,160.51
  5. Step 5: Solve for x
    x = 18,160.51/121.41
  6. Step 6: Final answer
    x = 149.58

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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.