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Finding the Fourth Proportional to 505.10, 757.70 and 139.89

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Solution

The fourth proportional to 505.10, 757.70 and 139.89 is: 209.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.10 : 757.70 = 139.89 : x
  2. Step 2: Convert to fraction form
    505.10/757.70 = 139.89/x
  3. Step 3: Cross multiply
    505.10x = 757.70 × 139.89
  4. Step 4: Simplify right side
    505.10x = 105,994.65
  5. Step 5: Solve for x
    x = 105,994.65/505.10
  6. Step 6: Final answer
    x = 209.85

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Similar ratio
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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.