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Finding the Fourth Proportional to 665.06, 996.20 and 390.32

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Solution

The fourth proportional to 665.06, 996.20 and 390.32 is: 584.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.06 : 996.20 = 390.32 : x
  2. Step 2: Convert to fraction form
    665.06/996.20 = 390.32/x
  3. Step 3: Cross multiply
    665.06x = 996.20 × 390.32
  4. Step 4: Simplify right side
    665.06x = 388,836.78
  5. Step 5: Solve for x
    x = 388,836.78/665.06
  6. Step 6: Final answer
    x = 584.66

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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.