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Finding the Fourth Proportional to 208.86, 314.57 and 198.78

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Solution

The fourth proportional to 208.86, 314.57 and 198.78 is: 299.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.86 : 314.57 = 198.78 : x
  2. Step 2: Convert to fraction form
    208.86/314.57 = 198.78/x
  3. Step 3: Cross multiply
    208.86x = 314.57 × 198.78
  4. Step 4: Simplify right side
    208.86x = 62,529.23
  5. Step 5: Solve for x
    x = 62,529.23/208.86
  6. Step 6: Final answer
    x = 299.38

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.