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Finding the Fourth Proportional to 665.13, 996.80 and 645.42

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Solution

The fourth proportional to 665.13, 996.80 and 645.42 is: 967.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.13 : 996.80 = 645.42 : x
  2. Step 2: Convert to fraction form
    665.13/996.80 = 645.42/x
  3. Step 3: Cross multiply
    665.13x = 996.80 × 645.42
  4. Step 4: Simplify right side
    665.13x = 643,351.43
  5. Step 5: Solve for x
    x = 643,351.43/665.13
  6. Step 6: Final answer
    x = 967.26

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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.