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Finding the Fourth Proportional to 121.35, 181.99 and 39.09

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Solution

The fourth proportional to 121.35, 181.99 and 39.09 is: 58.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    121.35 : 181.99 = 39.09 : x
  2. Step 2: Convert to fraction form
    121.35/181.99 = 39.09/x
  3. Step 3: Cross multiply
    121.35x = 181.99 × 39.09
  4. Step 4: Simplify right side
    121.35x = 7,113.72
  5. Step 5: Solve for x
    x = 7,113.72/121.35
  6. Step 6: Final answer
    x = 58.62

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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.