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Finding the Fourth Proportional to 280.74, 386.61 and 279.82

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Solution

The fourth proportional to 280.74, 386.61 and 279.82 is: 385.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.74 : 386.61 = 279.82 : x
  2. Step 2: Convert to fraction form
    280.74/386.61 = 279.82/x
  3. Step 3: Cross multiply
    280.74x = 386.61 × 279.82
  4. Step 4: Simplify right side
    280.74x = 108,179.81
  5. Step 5: Solve for x
    x = 108,179.81/280.74
  6. Step 6: Final answer
    x = 385.34

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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.