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Finding the Fourth Proportional to 800.35, 1,200.51 and 215.40

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Solution

The fourth proportional to 800.35, 1,200.51 and 215.40 is: 323.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.35 : 1,200.51 = 215.40 : x
  2. Step 2: Convert to fraction form
    800.35/1,200.51 = 215.40/x
  3. Step 3: Cross multiply
    800.35x = 1,200.51 × 215.40
  4. Step 4: Simplify right side
    800.35x = 258,589.85
  5. Step 5: Solve for x
    x = 258,589.85/800.35
  6. Step 6: Final answer
    x = 323.10

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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.