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Finding the Fourth Proportional to 306.86, 423.54 and 257.66

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Solution

The fourth proportional to 306.86, 423.54 and 257.66 is: 355.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.86 : 423.54 = 257.66 : x
  2. Step 2: Convert to fraction form
    306.86/423.54 = 257.66/x
  3. Step 3: Cross multiply
    306.86x = 423.54 × 257.66
  4. Step 4: Simplify right side
    306.86x = 109,127.20
  5. Step 5: Solve for x
    x = 109,127.20/306.86
  6. Step 6: Final answer
    x = 355.63

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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.