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Finding the Fourth Proportional to 306.30, 423.36 and 257.88

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Solution

The fourth proportional to 306.30, 423.36 and 257.88 is: 356.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.30 : 423.36 = 257.88 : x
  2. Step 2: Convert to fraction form
    306.30/423.36 = 257.88/x
  3. Step 3: Cross multiply
    306.30x = 423.36 × 257.88
  4. Step 4: Simplify right side
    306.30x = 109,176.08
  5. Step 5: Solve for x
    x = 109,176.08/306.30
  6. Step 6: Final answer
    x = 356.44

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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.