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Finding the Fourth Proportional to 306.28, 421.86 and 231.88

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Solution

The fourth proportional to 306.28, 421.86 and 231.88 is: 319.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.28 : 421.86 = 231.88 : x
  2. Step 2: Convert to fraction form
    306.28/421.86 = 231.88/x
  3. Step 3: Cross multiply
    306.28x = 421.86 × 231.88
  4. Step 4: Simplify right side
    306.28x = 97,820.90
  5. Step 5: Solve for x
    x = 97,820.90/306.28
  6. Step 6: Final answer
    x = 319.38

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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.