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Finding the Fourth Proportional to 290.21, 435.85 and 209.21

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Solution

The fourth proportional to 290.21, 435.85 and 209.21 is: 314.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.21 : 435.85 = 209.21 : x
  2. Step 2: Convert to fraction form
    290.21/435.85 = 209.21/x
  3. Step 3: Cross multiply
    290.21x = 435.85 × 209.21
  4. Step 4: Simplify right side
    290.21x = 91,181.48
  5. Step 5: Solve for x
    x = 91,181.48/290.21
  6. Step 6: Final answer
    x = 314.20

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.