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Finding the Fourth Proportional to 281.58, 421.81 and 213.18

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Solution

The fourth proportional to 281.58, 421.81 and 213.18 is: 319.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.58 : 421.81 = 213.18 : x
  2. Step 2: Convert to fraction form
    281.58/421.81 = 213.18/x
  3. Step 3: Cross multiply
    281.58x = 421.81 × 213.18
  4. Step 4: Simplify right side
    281.58x = 89,921.71
  5. Step 5: Solve for x
    x = 89,921.71/281.58
  6. Step 6: Final answer
    x = 319.35

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.