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Finding the Fourth Proportional to 400.90, 601.20 and 140.80

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Solution

The fourth proportional to 400.90, 601.20 and 140.80 is: 211.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    400.90 : 601.20 = 140.80 : x
  2. Step 2: Convert to fraction form
    400.90/601.20 = 140.80/x
  3. Step 3: Cross multiply
    400.90x = 601.20 × 140.80
  4. Step 4: Simplify right side
    400.90x = 84,648.96
  5. Step 5: Solve for x
    x = 84,648.96/400.90
  6. Step 6: Final answer
    x = 211.15

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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.