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Finding the Fourth Proportional to 209.40, 290.91 and 207.40

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Solution

The fourth proportional to 209.40, 290.91 and 207.40 is: 288.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    209.40 : 290.91 = 207.40 : x
  2. Step 2: Convert to fraction form
    209.40/290.91 = 207.40/x
  3. Step 3: Cross multiply
    209.40x = 290.91 × 207.40
  4. Step 4: Simplify right side
    209.40x = 60,334.73
  5. Step 5: Solve for x
    x = 60,334.73/209.40
  6. Step 6: Final answer
    x = 288.13

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.