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Finding the Fourth Proportional to 281.81, 423.16 and 212.40

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Solution

The fourth proportional to 281.81, 423.16 and 212.40 is: 318.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.81 : 423.16 = 212.40 : x
  2. Step 2: Convert to fraction form
    281.81/423.16 = 212.40/x
  3. Step 3: Cross multiply
    281.81x = 423.16 × 212.40
  4. Step 4: Simplify right side
    281.81x = 89,878.65
  5. Step 5: Solve for x
    x = 89,878.65/281.81
  6. Step 6: Final answer
    x = 318.94

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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.