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Finding the Fourth Proportional to 665.49, 998.23 and 512.40

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Solution

The fourth proportional to 665.49, 998.23 and 512.40 is: 768.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.49 : 998.23 = 512.40 : x
  2. Step 2: Convert to fraction form
    665.49/998.23 = 512.40/x
  3. Step 3: Cross multiply
    665.49x = 998.23 × 512.40
  4. Step 4: Simplify right side
    665.49x = 511,493.05
  5. Step 5: Solve for x
    x = 511,493.05/665.49
  6. Step 6: Final answer
    x = 768.60

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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.