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Finding the Fourth Proportional to 659.72, 989.60 and 221.00

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Solution

The fourth proportional to 659.72, 989.60 and 221.00 is: 331.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.72 : 989.60 = 221.00 : x
  2. Step 2: Convert to fraction form
    659.72/989.60 = 221.00/x
  3. Step 3: Cross multiply
    659.72x = 989.60 × 221.00
  4. Step 4: Simplify right side
    659.72x = 218,704.63
  5. Step 5: Solve for x
    x = 218,704.63/659.72
  6. Step 6: Final answer
    x = 331.51

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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.