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Finding the Fourth Proportional to 1,389.96, 2,083.73 and 660.15

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Solution

The fourth proportional to 1,389.96, 2,083.73 and 660.15 is: 989.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,389.96 : 2,083.73 = 660.15 : x
  2. Step 2: Convert to fraction form
    1,389.96/2,083.73 = 660.15/x
  3. Step 3: Cross multiply
    1,389.96x = 2,083.73 × 660.15
  4. Step 4: Simplify right side
    1,389.96x = 1,375,571.06
  5. Step 5: Solve for x
    x = 1,375,571.06/1,389.96
  6. Step 6: Final answer
    x = 989.65

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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.