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Finding the Fourth Proportional to 281.09, 387.63 and 218.81

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Solution

The fourth proportional to 281.09, 387.63 and 218.81 is: 301.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.09 : 387.63 = 218.81 : x
  2. Step 2: Convert to fraction form
    281.09/387.63 = 218.81/x
  3. Step 3: Cross multiply
    281.09x = 387.63 × 218.81
  4. Step 4: Simplify right side
    281.09x = 84,817.32
  5. Step 5: Solve for x
    x = 84,817.32/281.09
  6. Step 6: Final answer
    x = 301.74

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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.