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Finding the Fourth Proportional to 758.70, 1,138.05 and 394.20

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Solution

The fourth proportional to 758.70, 1,138.05 and 394.20 is: 591.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    758.70 : 1,138.05 = 394.20 : x
  2. Step 2: Convert to fraction form
    758.70/1,138.05 = 394.20/x
  3. Step 3: Cross multiply
    758.70x = 1,138.05 × 394.20
  4. Step 4: Simplify right side
    758.70x = 448,619.31
  5. Step 5: Solve for x
    x = 448,619.31/758.70
  6. Step 6: Final answer
    x = 591.30

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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.