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Finding the Fourth Proportional to 306.96, 423.28 and 208.56

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Solution

The fourth proportional to 306.96, 423.28 and 208.56 is: 287.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.96 : 423.28 = 208.56 : x
  2. Step 2: Convert to fraction form
    306.96/423.28 = 208.56/x
  3. Step 3: Cross multiply
    306.96x = 423.28 × 208.56
  4. Step 4: Simplify right side
    306.96x = 88,279.28
  5. Step 5: Solve for x
    x = 88,279.28/306.96
  6. Step 6: Final answer
    x = 287.59

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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.