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Finding the Fourth Proportional to 513.40, 770.13 and 205.21

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Solution

The fourth proportional to 513.40, 770.13 and 205.21 is: 307.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    513.40 : 770.13 = 205.21 : x
  2. Step 2: Convert to fraction form
    513.40/770.13 = 205.21/x
  3. Step 3: Cross multiply
    513.40x = 770.13 × 205.21
  4. Step 4: Simplify right side
    513.40x = 158,038.38
  5. Step 5: Solve for x
    x = 158,038.38/513.40
  6. Step 6: Final answer
    x = 307.83

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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.