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Finding the Fourth Proportional to 999.15, 1,378.86 and 579.49

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Solution

The fourth proportional to 999.15, 1,378.86 and 579.49 is: 799.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    999.15 : 1,378.86 = 579.49 : x
  2. Step 2: Convert to fraction form
    999.15/1,378.86 = 579.49/x
  3. Step 3: Cross multiply
    999.15x = 1,378.86 × 579.49
  4. Step 4: Simplify right side
    999.15x = 799,035.58
  5. Step 5: Solve for x
    x = 799,035.58/999.15
  6. Step 6: Final answer
    x = 799.72

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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.