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Finding the Fourth Proportional to 491.27, 678 and 281.47

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Solution

The fourth proportional to 491.27, 678 and 281.47 is: 388.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.27 : 678 = 281.47 : x
  2. Step 2: Convert to fraction form
    491.27/678 = 281.47/x
  3. Step 3: Cross multiply
    491.27x = 678 × 281.47
  4. Step 4: Simplify right side
    491.27x = 190,834.97
  5. Step 5: Solve for x
    x = 190,834.97/491.27
  6. Step 6: Final answer
    x = 388.45

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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.