Home / 1,422.05-2,129.43-989.51

Finding the Fourth Proportional to 1,422.05, 2,129.43 and 989.51

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Solution

The fourth proportional to 1,422.05, 2,129.43 and 989.51 is: 1,481.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,422.05 : 2,129.43 = 989.51 : x
  2. Step 2: Convert to fraction form
    1,422.05/2,129.43 = 989.51/x
  3. Step 3: Cross multiply
    1,422.05x = 2,129.43 × 989.51
  4. Step 4: Simplify right side
    1,422.05x = 2,107,092.28
  5. Step 5: Solve for x
    x = 2,107,092.28/1,422.05
  6. Step 6: Final answer
    x = 1,481.73

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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.