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Finding the Fourth Proportional to 304.75, 420.78 and 238.60

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Solution

The fourth proportional to 304.75, 420.78 and 238.60 is: 329.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    304.75 : 420.78 = 238.60 : x
  2. Step 2: Convert to fraction form
    304.75/420.78 = 238.60/x
  3. Step 3: Cross multiply
    304.75x = 420.78 × 238.60
  4. Step 4: Simplify right side
    304.75x = 100,398.11
  5. Step 5: Solve for x
    x = 100,398.11/304.75
  6. Step 6: Final answer
    x = 329.44

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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.