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Finding the Fourth Proportional to 279.45, 387.38 and 274.39

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Solution

The fourth proportional to 279.45, 387.38 and 274.39 is: 380.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.45 : 387.38 = 274.39 : x
  2. Step 2: Convert to fraction form
    279.45/387.38 = 274.39/x
  3. Step 3: Cross multiply
    279.45x = 387.38 × 274.39
  4. Step 4: Simplify right side
    279.45x = 106,292.92
  5. Step 5: Solve for x
    x = 106,292.92/279.45
  6. Step 6: Final answer
    x = 380.36

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.