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Finding the Fourth Proportional to 128.80, 192.12 and 124.95

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Solution

The fourth proportional to 128.80, 192.12 and 124.95 is: 186.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.80 : 192.12 = 124.95 : x
  2. Step 2: Convert to fraction form
    128.80/192.12 = 124.95/x
  3. Step 3: Cross multiply
    128.80x = 192.12 × 124.95
  4. Step 4: Simplify right side
    128.80x = 24,005.65
  5. Step 5: Solve for x
    x = 24,005.65/128.80
  6. Step 6: Final answer
    x = 186.38

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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.