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Finding the Fourth Proportional to 281.04, 387.89 and 215.70

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Solution

The fourth proportional to 281.04, 387.89 and 215.70 is: 297.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.04 : 387.89 = 215.70 : x
  2. Step 2: Convert to fraction form
    281.04/387.89 = 215.70/x
  3. Step 3: Cross multiply
    281.04x = 387.89 × 215.70
  4. Step 4: Simplify right side
    281.04x = 83,667.87
  5. Step 5: Solve for x
    x = 83,667.87/281.04
  6. Step 6: Final answer
    x = 297.71

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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.