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Finding the Fourth Proportional to 512.86, 769.29 and 128.11

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Solution

The fourth proportional to 512.86, 769.29 and 128.11 is: 192.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    512.86 : 769.29 = 128.11 : x
  2. Step 2: Convert to fraction form
    512.86/769.29 = 128.11/x
  3. Step 3: Cross multiply
    512.86x = 769.29 × 128.11
  4. Step 4: Simplify right side
    512.86x = 98,553.26
  5. Step 5: Solve for x
    x = 98,553.26/512.86
  6. Step 6: Final answer
    x = 192.16

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Similar ratio
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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.