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Finding the Fourth Proportional to 513.62, 770.41 and 128.87

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Solution

The fourth proportional to 513.62, 770.41 and 128.87 is: 193.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    513.62 : 770.41 = 128.87 : x
  2. Step 2: Convert to fraction form
    513.62/770.41 = 128.87/x
  3. Step 3: Cross multiply
    513.62x = 770.41 × 128.87
  4. Step 4: Simplify right side
    513.62x = 99,282.74
  5. Step 5: Solve for x
    x = 99,282.74/513.62
  6. Step 6: Final answer
    x = 193.30

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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.