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Finding the Fourth Proportional to 280.20, 386.73 and 261.30

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Solution

The fourth proportional to 280.20, 386.73 and 261.30 is: 360.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.20 : 386.73 = 261.30 : x
  2. Step 2: Convert to fraction form
    280.20/386.73 = 261.30/x
  3. Step 3: Cross multiply
    280.20x = 386.73 × 261.30
  4. Step 4: Simplify right side
    280.20x = 101,052.55
  5. Step 5: Solve for x
    x = 101,052.55/280.20
  6. Step 6: Final answer
    x = 360.64

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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.