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Finding the Fourth Proportional to 659.85, 989.75 and 369.20

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Solution

The fourth proportional to 659.85, 989.75 and 369.20 is: 553.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.85 : 989.75 = 369.20 : x
  2. Step 2: Convert to fraction form
    659.85/989.75 = 369.20/x
  3. Step 3: Cross multiply
    659.85x = 989.75 × 369.20
  4. Step 4: Simplify right side
    659.85x = 365,412.30
  5. Step 5: Solve for x
    x = 365,412.30/659.85
  6. Step 6: Final answer
    x = 553.78

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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.