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Finding the Fourth Proportional to 512.92, 769.40 and 128.18

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Solution

The fourth proportional to 512.92, 769.40 and 128.18 is: 192.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    512.92 : 769.40 = 128.18 : x
  2. Step 2: Convert to fraction form
    512.92/769.40 = 128.18/x
  3. Step 3: Cross multiply
    512.92x = 769.40 × 128.18
  4. Step 4: Simplify right side
    512.92x = 98,621.69
  5. Step 5: Solve for x
    x = 98,621.69/512.92
  6. Step 6: Final answer
    x = 192.27

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Double scale
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Similar ratio
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1.5x scale

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.