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Finding the Fourth Proportional to 513.55, 770.40 and 205.39

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Solution

The fourth proportional to 513.55, 770.40 and 205.39 is: 308.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    513.55 : 770.40 = 205.39 : x
  2. Step 2: Convert to fraction form
    513.55/770.40 = 205.39/x
  3. Step 3: Cross multiply
    513.55x = 770.40 × 205.39
  4. Step 4: Simplify right side
    513.55x = 158,232.46
  5. Step 5: Solve for x
    x = 158,232.46/513.55
  6. Step 6: Final answer
    x = 308.11

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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.