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Finding the Fourth Proportional to 491.20, 678 and 325.54

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Solution

The fourth proportional to 491.20, 678 and 325.54 is: 449.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.20 : 678 = 325.54 : x
  2. Step 2: Convert to fraction form
    491.20/678 = 325.54/x
  3. Step 3: Cross multiply
    491.20x = 678 × 325.54
  4. Step 4: Simplify right side
    491.20x = 220,716.12
  5. Step 5: Solve for x
    x = 220,716.12/491.20
  6. Step 6: Final answer
    x = 449.34

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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.