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Finding the Fourth Proportional to 491.39, 678.31 and 325.54

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Solution

The fourth proportional to 491.39, 678.31 and 325.54 is: 449.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.39 : 678.31 = 325.54 : x
  2. Step 2: Convert to fraction form
    491.39/678.31 = 325.54/x
  3. Step 3: Cross multiply
    491.39x = 678.31 × 325.54
  4. Step 4: Simplify right side
    491.39x = 220,820.35
  5. Step 5: Solve for x
    x = 220,820.35/491.39
  6. Step 6: Final answer
    x = 449.38

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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.