Home / 1,389.62-1,917.87-800.15

Finding the Fourth Proportional to 1,389.62, 1,917.87 and 800.15

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Solution

The fourth proportional to 1,389.62, 1,917.87 and 800.15 is: 1,104.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,389.62 : 1,917.87 = 800.15 : x
  2. Step 2: Convert to fraction form
    1,389.62/1,917.87 = 800.15/x
  3. Step 3: Cross multiply
    1,389.62x = 1,917.87 × 800.15
  4. Step 4: Simplify right side
    1,389.62x = 1,534,583.68
  5. Step 5: Solve for x
    x = 1,534,583.68/1,389.62
  6. Step 6: Final answer
    x = 1,104.32

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.