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Finding the Fourth Proportional to 290.85, 400.91 and 212.19

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Solution

The fourth proportional to 290.85, 400.91 and 212.19 is: 292.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.85 : 400.91 = 212.19 : x
  2. Step 2: Convert to fraction form
    290.85/400.91 = 212.19/x
  3. Step 3: Cross multiply
    290.85x = 400.91 × 212.19
  4. Step 4: Simplify right side
    290.85x = 85,068.03
  5. Step 5: Solve for x
    x = 85,068.03/290.85
  6. Step 6: Final answer
    x = 292.48

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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.