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Finding the Fourth Proportional to 758.70, 1,138.37 and 320.05

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Solution

The fourth proportional to 758.70, 1,138.37 and 320.05 is: 480.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    758.70 : 1,138.37 = 320.05 : x
  2. Step 2: Convert to fraction form
    758.70/1,138.37 = 320.05/x
  3. Step 3: Cross multiply
    758.70x = 1,138.37 × 320.05
  4. Step 4: Simplify right side
    758.70x = 364,336.94
  5. Step 5: Solve for x
    x = 364,336.94/758.70
  6. Step 6: Final answer
    x = 480.21

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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.