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Finding the Fourth Proportional to 280.91, 387.60 and 170.39

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Solution

The fourth proportional to 280.91, 387.60 and 170.39 is: 235.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.91 : 387.60 = 170.39 : x
  2. Step 2: Convert to fraction form
    280.91/387.60 = 170.39/x
  3. Step 3: Cross multiply
    280.91x = 387.60 × 170.39
  4. Step 4: Simplify right side
    280.91x = 66,042.31
  5. Step 5: Solve for x
    x = 66,042.31/280.91
  6. Step 6: Final answer
    x = 235.10

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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.