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Finding the Fourth Proportional to 280.39, 386.85 and 191.80

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Solution

The fourth proportional to 280.39, 386.85 and 191.80 is: 264.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.39 : 386.85 = 191.80 : x
  2. Step 2: Convert to fraction form
    280.39/386.85 = 191.80/x
  3. Step 3: Cross multiply
    280.39x = 386.85 × 191.80
  4. Step 4: Simplify right side
    280.39x = 74,196.38
  5. Step 5: Solve for x
    x = 74,196.38/280.39
  6. Step 6: Final answer
    x = 264.62

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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.