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Finding the Fourth Proportional to 290.57, 401.34 and 217.21

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Solution

The fourth proportional to 290.57, 401.34 and 217.21 is: 300.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.57 : 401.34 = 217.21 : x
  2. Step 2: Convert to fraction form
    290.57/401.34 = 217.21/x
  3. Step 3: Cross multiply
    290.57x = 401.34 × 217.21
  4. Step 4: Simplify right side
    290.57x = 87,173.98
  5. Step 5: Solve for x
    x = 87,173.98/290.57
  6. Step 6: Final answer
    x = 300.02

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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.