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Finding the Fourth Proportional to 213.02, 319.68 and 121.80

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Solution

The fourth proportional to 213.02, 319.68 and 121.80 is: 182.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    213.02 : 319.68 = 121.80 : x
  2. Step 2: Convert to fraction form
    213.02/319.68 = 121.80/x
  3. Step 3: Cross multiply
    213.02x = 319.68 × 121.80
  4. Step 4: Simplify right side
    213.02x = 38,937.02
  5. Step 5: Solve for x
    x = 38,937.02/213.02
  6. Step 6: Final answer
    x = 182.79

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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.