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Finding the Fourth Proportional to 820.58, 1,230.86 and 300.57

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Solution

The fourth proportional to 820.58, 1,230.86 and 300.57 is: 450.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.58 : 1,230.86 = 300.57 : x
  2. Step 2: Convert to fraction form
    820.58/1,230.86 = 300.57/x
  3. Step 3: Cross multiply
    820.58x = 1,230.86 × 300.57
  4. Step 4: Simplify right side
    820.58x = 369,958.09
  5. Step 5: Solve for x
    x = 369,958.09/820.58
  6. Step 6: Final answer
    x = 450.85

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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.