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Finding the Fourth Proportional to 171.32, 256.98 and 139.19

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Solution

The fourth proportional to 171.32, 256.98 and 139.19 is: 208.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    171.32 : 256.98 = 139.19 : x
  2. Step 2: Convert to fraction form
    171.32/256.98 = 139.19/x
  3. Step 3: Cross multiply
    171.32x = 256.98 × 139.19
  4. Step 4: Simplify right side
    171.32x = 35,769.05
  5. Step 5: Solve for x
    x = 35,769.05/171.32
  6. Step 6: Final answer
    x = 208.79

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.