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Finding the Fourth Proportional to 1,999.80, 2,998.80 and 766.80

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Solution

The fourth proportional to 1,999.80, 2,998.80 and 766.80 is: 1,149.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,999.80 : 2,998.80 = 766.80 : x
  2. Step 2: Convert to fraction form
    1,999.80/2,998.80 = 766.80/x
  3. Step 3: Cross multiply
    1,999.80x = 2,998.80 × 766.80
  4. Step 4: Simplify right side
    1,999.80x = 2,299,479.84
  5. Step 5: Solve for x
    x = 2,299,479.84/1,999.80
  6. Step 6: Final answer
    x = 1,149.85

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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.