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Finding the Fourth Proportional to 491.09, 681.19 and 478.94

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Solution

The fourth proportional to 491.09, 681.19 and 478.94 is: 664.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.09 : 681.19 = 478.94 : x
  2. Step 2: Convert to fraction form
    491.09/681.19 = 478.94/x
  3. Step 3: Cross multiply
    491.09x = 681.19 × 478.94
  4. Step 4: Simplify right side
    491.09x = 326,244.54
  5. Step 5: Solve for x
    x = 326,244.54/491.09
  6. Step 6: Final answer
    x = 664.33

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.