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Finding the Fourth Proportional to 290.35, 400.21 and 211.69

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Solution

The fourth proportional to 290.35, 400.21 and 211.69 is: 291.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.35 : 400.21 = 211.69 : x
  2. Step 2: Convert to fraction form
    290.35/400.21 = 211.69/x
  3. Step 3: Cross multiply
    290.35x = 400.21 × 211.69
  4. Step 4: Simplify right side
    290.35x = 84,720.45
  5. Step 5: Solve for x
    x = 84,720.45/290.35
  6. Step 6: Final answer
    x = 291.79

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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.