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Finding the Fourth Proportional to 170.80, 255.84 and 138.40

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Solution

The fourth proportional to 170.80, 255.84 and 138.40 is: 207.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    170.80 : 255.84 = 138.40 : x
  2. Step 2: Convert to fraction form
    170.80/255.84 = 138.40/x
  3. Step 3: Cross multiply
    170.80x = 255.84 × 138.40
  4. Step 4: Simplify right side
    170.80x = 35,408.26
  5. Step 5: Solve for x
    x = 35,408.26/170.80
  6. Step 6: Final answer
    x = 207.31

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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.