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Finding the Fourth Proportional to 290.39, 401.30 and 220.39

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Solution

The fourth proportional to 290.39, 401.30 and 220.39 is: 304.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.39 : 401.30 = 220.39 : x
  2. Step 2: Convert to fraction form
    290.39/401.30 = 220.39/x
  3. Step 3: Cross multiply
    290.39x = 401.30 × 220.39
  4. Step 4: Simplify right side
    290.39x = 88,441.41
  5. Step 5: Solve for x
    x = 88,441.41/290.39
  6. Step 6: Final answer
    x = 304.56

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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.