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Finding the Fourth Proportional to 209.40, 288.30 and 198.60

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Solution

The fourth proportional to 209.40, 288.30 and 198.60 is: 273.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    209.40 : 288.30 = 198.60 : x
  2. Step 2: Convert to fraction form
    209.40/288.30 = 198.60/x
  3. Step 3: Cross multiply
    209.40x = 288.30 × 198.60
  4. Step 4: Simplify right side
    209.40x = 57,256.38
  5. Step 5: Solve for x
    x = 57,256.38/209.40
  6. Step 6: Final answer
    x = 273.43

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.