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Finding the Fourth Proportional to 290.20, 399.89 and 216.35

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Solution

The fourth proportional to 290.20, 399.89 and 216.35 is: 298.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.20 : 399.89 = 216.35 : x
  2. Step 2: Convert to fraction form
    290.20/399.89 = 216.35/x
  3. Step 3: Cross multiply
    290.20x = 399.89 × 216.35
  4. Step 4: Simplify right side
    290.20x = 86,515.12
  5. Step 5: Solve for x
    x = 86,515.12/290.20
  6. Step 6: Final answer
    x = 298.13

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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.