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Finding the Fourth Proportional to 185.80, 278.84 and 128.12

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Solution

The fourth proportional to 185.80, 278.84 and 128.12 is: 192.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    185.80 : 278.84 = 128.12 : x
  2. Step 2: Convert to fraction form
    185.80/278.84 = 128.12/x
  3. Step 3: Cross multiply
    185.80x = 278.84 × 128.12
  4. Step 4: Simplify right side
    185.80x = 35,724.98
  5. Step 5: Solve for x
    x = 35,724.98/185.80
  6. Step 6: Final answer
    x = 192.28

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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.