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Finding the Fourth Proportional to 281.70, 387.90 and 275.31

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Solution

The fourth proportional to 281.70, 387.90 and 275.31 is: 379.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.70 : 387.90 = 275.31 : x
  2. Step 2: Convert to fraction form
    281.70/387.90 = 275.31/x
  3. Step 3: Cross multiply
    281.70x = 387.90 × 275.31
  4. Step 4: Simplify right side
    281.70x = 106,792.75
  5. Step 5: Solve for x
    x = 106,792.75/281.70
  6. Step 6: Final answer
    x = 379.10

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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.