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Finding the Fourth Proportional to 306.42, 422.91 and 208.11

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Solution

The fourth proportional to 306.42, 422.91 and 208.11 is: 287.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.42 : 422.91 = 208.11 : x
  2. Step 2: Convert to fraction form
    306.42/422.91 = 208.11/x
  3. Step 3: Cross multiply
    306.42x = 422.91 × 208.11
  4. Step 4: Simplify right side
    306.42x = 88,011.80
  5. Step 5: Solve for x
    x = 88,011.80/306.42
  6. Step 6: Final answer
    x = 287.23

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.