Home / 1,438.20-2,151.81-789.39

Finding the Fourth Proportional to 1,438.20, 2,151.81 and 789.39

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Solution

The fourth proportional to 1,438.20, 2,151.81 and 789.39 is: 1,181.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,438.20 : 2,151.81 = 789.39 : x
  2. Step 2: Convert to fraction form
    1,438.20/2,151.81 = 789.39/x
  3. Step 3: Cross multiply
    1,438.20x = 2,151.81 × 789.39
  4. Step 4: Simplify right side
    1,438.20x = 1,698,617.30
  5. Step 5: Solve for x
    x = 1,698,617.30/1,438.20
  6. Step 6: Final answer
    x = 1,181.07

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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.