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Finding the Fourth Proportional to 389.70, 584.10 and 216.15

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Solution

The fourth proportional to 389.70, 584.10 and 216.15 is: 323.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.70 : 584.10 = 216.15 : x
  2. Step 2: Convert to fraction form
    389.70/584.10 = 216.15/x
  3. Step 3: Cross multiply
    389.70x = 584.10 × 216.15
  4. Step 4: Simplify right side
    389.70x = 126,253.22
  5. Step 5: Solve for x
    x = 126,253.22/389.70
  6. Step 6: Final answer
    x = 323.98

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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.