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Finding the Fourth Proportional to 659.58, 989.40 and 220.86

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Solution

The fourth proportional to 659.58, 989.40 and 220.86 is: 331.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.58 : 989.40 = 220.86 : x
  2. Step 2: Convert to fraction form
    659.58/989.40 = 220.86/x
  3. Step 3: Cross multiply
    659.58x = 989.40 × 220.86
  4. Step 4: Simplify right side
    659.58x = 218,519.71
  5. Step 5: Solve for x
    x = 218,519.71/659.58
  6. Step 6: Final answer
    x = 331.30

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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.