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Finding the Fourth Proportional to 208.85, 310.80 and 206.69

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Solution

The fourth proportional to 208.85, 310.80 and 206.69 is: 307.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.85 : 310.80 = 206.69 : x
  2. Step 2: Convert to fraction form
    208.85/310.80 = 206.69/x
  3. Step 3: Cross multiply
    208.85x = 310.80 × 206.69
  4. Step 4: Simplify right side
    208.85x = 64,239.77
  5. Step 5: Solve for x
    x = 64,239.77/208.85
  6. Step 6: Final answer
    x = 307.59

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.