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Finding the Fourth Proportional to 3,128, 4,692 and 819.50

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Solution

The fourth proportional to 3,128, 4,692 and 819.50 is: 1,229.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    3,128 : 4,692 = 819.50 : x
  2. Step 2: Convert to fraction form
    3,128/4,692 = 819.50/x
  3. Step 3: Cross multiply
    3,128x = 4,692 × 819.50
  4. Step 4: Simplify right side
    3,128x = 3,845,094
  5. Step 5: Solve for x
    x = 3,845,094/3,128
  6. Step 6: Final answer
    x = 1,229.25

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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.