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Finding the Fourth Proportional to 665.86, 998.80 and 512.78

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Solution

The fourth proportional to 665.86, 998.80 and 512.78 is: 769.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.86 : 998.80 = 512.78 : x
  2. Step 2: Convert to fraction form
    665.86/998.80 = 512.78/x
  3. Step 3: Cross multiply
    665.86x = 998.80 × 512.78
  4. Step 4: Simplify right side
    665.86x = 512,164.66
  5. Step 5: Solve for x
    x = 512,164.66/665.86
  6. Step 6: Final answer
    x = 769.18

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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.