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Finding the Fourth Proportional to 389.85, 537.98 and 215.18

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Solution

The fourth proportional to 389.85, 537.98 and 215.18 is: 296.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.85 : 537.98 = 215.18 : x
  2. Step 2: Convert to fraction form
    389.85/537.98 = 215.18/x
  3. Step 3: Cross multiply
    389.85x = 537.98 × 215.18
  4. Step 4: Simplify right side
    389.85x = 115,762.54
  5. Step 5: Solve for x
    x = 115,762.54/389.85
  6. Step 6: Final answer
    x = 296.94

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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.