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Finding the Fourth Proportional to 389.30, 537.26 and 221.29

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Solution

The fourth proportional to 389.30, 537.26 and 221.29 is: 305.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.30 : 537.26 = 221.29 : x
  2. Step 2: Convert to fraction form
    389.30/537.26 = 221.29/x
  3. Step 3: Cross multiply
    389.30x = 537.26 × 221.29
  4. Step 4: Simplify right side
    389.30x = 118,890.27
  5. Step 5: Solve for x
    x = 118,890.27/389.30
  6. Step 6: Final answer
    x = 305.39

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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.