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Finding the Fourth Proportional to 661.33, 991.89 and 222.61

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Solution

The fourth proportional to 661.33, 991.89 and 222.61 is: 333.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.33 : 991.89 = 222.61 : x
  2. Step 2: Convert to fraction form
    661.33/991.89 = 222.61/x
  3. Step 3: Cross multiply
    661.33x = 991.89 × 222.61
  4. Step 4: Simplify right side
    661.33x = 220,804.63
  5. Step 5: Solve for x
    x = 220,804.63/661.33
  6. Step 6: Final answer
    x = 333.88

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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.