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Finding the Fourth Proportional to 513.50, 770.26 and 128.76

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Solution

The fourth proportional to 513.50, 770.26 and 128.76 is: 193.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    513.50 : 770.26 = 128.76 : x
  2. Step 2: Convert to fraction form
    513.50/770.26 = 128.76/x
  3. Step 3: Cross multiply
    513.50x = 770.26 × 128.76
  4. Step 4: Simplify right side
    513.50x = 99,178.68
  5. Step 5: Solve for x
    x = 99,178.68/513.50
  6. Step 6: Final answer
    x = 193.14

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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.