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Finding the Fourth Proportional to 259.20, 388.38 and 208.18

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Solution

The fourth proportional to 259.20, 388.38 and 208.18 is: 311.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    259.20 : 388.38 = 208.18 : x
  2. Step 2: Convert to fraction form
    259.20/388.38 = 208.18/x
  3. Step 3: Cross multiply
    259.20x = 388.38 × 208.18
  4. Step 4: Simplify right side
    259.20x = 80,852.95
  5. Step 5: Solve for x
    x = 80,852.95/259.20
  6. Step 6: Final answer
    x = 311.93

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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.