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Finding the Fourth Proportional to 321.27, 440.78 and 305.79

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Solution

The fourth proportional to 321.27, 440.78 and 305.79 is: 419.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    321.27 : 440.78 = 305.79 : x
  2. Step 2: Convert to fraction form
    321.27/440.78 = 305.79/x
  3. Step 3: Cross multiply
    321.27x = 440.78 × 305.79
  4. Step 4: Simplify right side
    321.27x = 134,784.59
  5. Step 5: Solve for x
    x = 134,784.59/321.27
  6. Step 6: Final answer
    x = 419.54

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.