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Finding the Fourth Proportional to 665.36, 998.40 and 630.80

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Solution

The fourth proportional to 665.36, 998.40 and 630.80 is: 946.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.36 : 998.40 = 630.80 : x
  2. Step 2: Convert to fraction form
    665.36/998.40 = 630.80/x
  3. Step 3: Cross multiply
    665.36x = 998.40 × 630.80
  4. Step 4: Simplify right side
    665.36x = 629,790.72
  5. Step 5: Solve for x
    x = 629,790.72/665.36
  6. Step 6: Final answer
    x = 946.54

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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.