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Finding the Fourth Proportional to 278.70, 386.23 and 274.79

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Solution

The fourth proportional to 278.70, 386.23 and 274.79 is: 380.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.70 : 386.23 = 274.79 : x
  2. Step 2: Convert to fraction form
    278.70/386.23 = 274.79/x
  3. Step 3: Cross multiply
    278.70x = 386.23 × 274.79
  4. Step 4: Simplify right side
    278.70x = 106,130.55
  5. Step 5: Solve for x
    x = 106,130.55/278.70
  6. Step 6: Final answer
    x = 380.81

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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.