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Finding the Fourth Proportional to 505.80, 758.78 and 140.60

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Solution

The fourth proportional to 505.80, 758.78 and 140.60 is: 210.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.80 : 758.78 = 140.60 : x
  2. Step 2: Convert to fraction form
    505.80/758.78 = 140.60/x
  3. Step 3: Cross multiply
    505.80x = 758.78 × 140.60
  4. Step 4: Simplify right side
    505.80x = 106,679.97
  5. Step 5: Solve for x
    x = 106,679.97/505.80
  6. Step 6: Final answer
    x = 210.91

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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.