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Finding the Fourth Proportional to 758.90, 1,138.35 and 320.15

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Solution

The fourth proportional to 758.90, 1,138.35 and 320.15 is: 480.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    758.90 : 1,138.35 = 320.15 : x
  2. Step 2: Convert to fraction form
    758.90/1,138.35 = 320.15/x
  3. Step 3: Cross multiply
    758.90x = 1,138.35 × 320.15
  4. Step 4: Simplify right side
    758.90x = 364,441.33
  5. Step 5: Solve for x
    x = 364,441.33/758.90
  6. Step 6: Final answer
    x = 480.23

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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.