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Finding the Fourth Proportional to 819.50, 1,228.44 and 380.89

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Solution

The fourth proportional to 819.50, 1,228.44 and 380.89 is: 570.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    819.50 : 1,228.44 = 380.89 : x
  2. Step 2: Convert to fraction form
    819.50/1,228.44 = 380.89/x
  3. Step 3: Cross multiply
    819.50x = 1,228.44 × 380.89
  4. Step 4: Simplify right side
    819.50x = 467,898.87
  5. Step 5: Solve for x
    x = 467,898.87/819.50
  6. Step 6: Final answer
    x = 570.95

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1.5x scale

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.