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Finding the Fourth Proportional to 128.82, 194.30 and 121.33

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Solution

The fourth proportional to 128.82, 194.30 and 121.33 is: 183.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.82 : 194.30 = 121.33 : x
  2. Step 2: Convert to fraction form
    128.82/194.30 = 121.33/x
  3. Step 3: Cross multiply
    128.82x = 194.30 × 121.33
  4. Step 4: Simplify right side
    128.82x = 23,574.42
  5. Step 5: Solve for x
    x = 23,574.42/128.82
  6. Step 6: Final answer
    x = 183.00

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.