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Finding the Fourth Proportional to 659.42, 989.20 and 220.66

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Solution

The fourth proportional to 659.42, 989.20 and 220.66 is: 331.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.42 : 989.20 = 220.66 : x
  2. Step 2: Convert to fraction form
    659.42/989.20 = 220.66/x
  3. Step 3: Cross multiply
    659.42x = 989.20 × 220.66
  4. Step 4: Simplify right side
    659.42x = 218,273.43
  5. Step 5: Solve for x
    x = 218,273.43/659.42
  6. Step 6: Final answer
    x = 331.01

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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.