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Finding the Fourth Proportional to 908.80, 1,254.40 and 819.20

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Solution

The fourth proportional to 908.80, 1,254.40 and 819.20 is: 1,130.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    908.80 : 1,254.40 = 819.20 : x
  2. Step 2: Convert to fraction form
    908.80/1,254.40 = 819.20/x
  3. Step 3: Cross multiply
    908.80x = 1,254.40 × 819.20
  4. Step 4: Simplify right side
    908.80x = 1,027,604.48
  5. Step 5: Solve for x
    x = 1,027,604.48/908.80
  6. Step 6: Final answer
    x = 1,130.73

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.