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Finding the Fourth Proportional to 209.85, 310.38 and 209.85

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Solution

The fourth proportional to 209.85, 310.38 and 209.85 is: 310.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    209.85 : 310.38 = 209.85 : x
  2. Step 2: Convert to fraction form
    209.85/310.38 = 209.85/x
  3. Step 3: Cross multiply
    209.85x = 310.38 × 209.85
  4. Step 4: Simplify right side
    209.85x = 65,133.24
  5. Step 5: Solve for x
    x = 65,133.24/209.85
  6. Step 6: Final answer
    x = 310.38

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Why These Related Problems?

These problems maintain the same ratio (1.48) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.