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Finding the Fourth Proportional to 512.98, 769.47 and 128.23

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Solution

The fourth proportional to 512.98, 769.47 and 128.23 is: 192.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    512.98 : 769.47 = 128.23 : x
  2. Step 2: Convert to fraction form
    512.98/769.47 = 128.23/x
  3. Step 3: Cross multiply
    512.98x = 769.47 × 128.23
  4. Step 4: Simplify right side
    512.98x = 98,665.89
  5. Step 5: Solve for x
    x = 98,665.89/512.98
  6. Step 6: Final answer
    x = 192.34

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Half scale
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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.