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Finding the Fourth Proportional to 259.30, 388.23 and 213.58

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Solution

The fourth proportional to 259.30, 388.23 and 213.58 is: 319.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    259.30 : 388.23 = 213.58 : x
  2. Step 2: Convert to fraction form
    259.30/388.23 = 213.58/x
  3. Step 3: Cross multiply
    259.30x = 388.23 × 213.58
  4. Step 4: Simplify right side
    259.30x = 82,918.16
  5. Step 5: Solve for x
    x = 82,918.16/259.30
  6. Step 6: Final answer
    x = 319.78

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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.