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Finding the Fourth Proportional to 170.80, 256.20 and 140.80

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Solution

The fourth proportional to 170.80, 256.20 and 140.80 is: 211.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    170.80 : 256.20 = 140.80 : x
  2. Step 2: Convert to fraction form
    170.80/256.20 = 140.80/x
  3. Step 3: Cross multiply
    170.80x = 256.20 × 140.80
  4. Step 4: Simplify right side
    170.80x = 36,072.96
  5. Step 5: Solve for x
    x = 36,072.96/170.80
  6. Step 6: Final answer
    x = 211.20

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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.