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Finding the Fourth Proportional to 260.86, 390.78 and 199.69

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Solution

The fourth proportional to 260.86, 390.78 and 199.69 is: 299.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    260.86 : 390.78 = 199.69 : x
  2. Step 2: Convert to fraction form
    260.86/390.78 = 199.69/x
  3. Step 3: Cross multiply
    260.86x = 390.78 × 199.69
  4. Step 4: Simplify right side
    260.86x = 78,035.80
  5. Step 5: Solve for x
    x = 78,035.80/260.86
  6. Step 6: Final answer
    x = 299.15

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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.