Home / 1,986.20-2,979.30-1,208.60

Finding the Fourth Proportional to 1,986.20, 2,979.30 and 1,208.60

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Solution

The fourth proportional to 1,986.20, 2,979.30 and 1,208.60 is: 1,812.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,986.20 : 2,979.30 = 1,208.60 : x
  2. Step 2: Convert to fraction form
    1,986.20/2,979.30 = 1,208.60/x
  3. Step 3: Cross multiply
    1,986.20x = 2,979.30 × 1,208.60
  4. Step 4: Simplify right side
    1,986.20x = 3,600,781.98
  5. Step 5: Solve for x
    x = 3,600,781.98/1,986.20
  6. Step 6: Final answer
    x = 1,812.90

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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.