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Finding the Fourth Proportional to 259.05, 388.35 and 128.97

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Solution

The fourth proportional to 259.05, 388.35 and 128.97 is: 193.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    259.05 : 388.35 = 128.97 : x
  2. Step 2: Convert to fraction form
    259.05/388.35 = 128.97/x
  3. Step 3: Cross multiply
    259.05x = 388.35 × 128.97
  4. Step 4: Simplify right side
    259.05x = 50,085.50
  5. Step 5: Solve for x
    x = 50,085.50/259.05
  6. Step 6: Final answer
    x = 193.34

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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.