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Finding the Fourth Proportional to 513.70, 770.55 and 128.95

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Solution

The fourth proportional to 513.70, 770.55 and 128.95 is: 193.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    513.70 : 770.55 = 128.95 : x
  2. Step 2: Convert to fraction form
    513.70/770.55 = 128.95/x
  3. Step 3: Cross multiply
    513.70x = 770.55 × 128.95
  4. Step 4: Simplify right side
    513.70x = 99,362.42
  5. Step 5: Solve for x
    x = 99,362.42/513.70
  6. Step 6: Final answer
    x = 193.43

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Double scale
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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.