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Finding the Fourth Proportional to 280.76, 387.42 and 170.28

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Solution

The fourth proportional to 280.76, 387.42 and 170.28 is: 234.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.76 : 387.42 = 170.28 : x
  2. Step 2: Convert to fraction form
    280.76/387.42 = 170.28/x
  3. Step 3: Cross multiply
    280.76x = 387.42 × 170.28
  4. Step 4: Simplify right side
    280.76x = 65,969.88
  5. Step 5: Solve for x
    x = 65,969.88/280.76
  6. Step 6: Final answer
    x = 234.97

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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.