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Finding the Fourth Proportional to 138.00, 206.04 and 121.60

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Solution

The fourth proportional to 138.00, 206.04 and 121.60 is: 181.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.00 : 206.04 = 121.60 : x
  2. Step 2: Convert to fraction form
    138.00/206.04 = 121.60/x
  3. Step 3: Cross multiply
    138.00x = 206.04 × 121.60
  4. Step 4: Simplify right side
    138.00x = 25,055.18
  5. Step 5: Solve for x
    x = 25,055.18/138.00
  6. Step 6: Final answer
    x = 181.55

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.