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Finding the Fourth Proportional to 666.20, 998.78 and 447.05

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Solution

The fourth proportional to 666.20, 998.78 and 447.05 is: 670.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.20 : 998.78 = 447.05 : x
  2. Step 2: Convert to fraction form
    666.20/998.78 = 447.05/x
  3. Step 3: Cross multiply
    666.20x = 998.78 × 447.05
  4. Step 4: Simplify right side
    666.20x = 446,504.86
  5. Step 5: Solve for x
    x = 446,504.86/666.20
  6. Step 6: Final answer
    x = 670.22

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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.