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Finding the Fourth Proportional to 280.43, 386.81 and 185.90

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Solution

The fourth proportional to 280.43, 386.81 and 185.90 is: 256.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.43 : 386.81 = 185.90 : x
  2. Step 2: Convert to fraction form
    280.43/386.81 = 185.90/x
  3. Step 3: Cross multiply
    280.43x = 386.81 × 185.90
  4. Step 4: Simplify right side
    280.43x = 71,905.81
  5. Step 5: Solve for x
    x = 71,905.81/280.43
  6. Step 6: Final answer
    x = 256.41

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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.