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Finding the Fourth Proportional to 1,389.09, 1,917.05 and 799.64

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Solution

The fourth proportional to 1,389.09, 1,917.05 and 799.64 is: 1,103.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,389.09 : 1,917.05 = 799.64 : x
  2. Step 2: Convert to fraction form
    1,389.09/1,917.05 = 799.64/x
  3. Step 3: Cross multiply
    1,389.09x = 1,917.05 × 799.64
  4. Step 4: Simplify right side
    1,389.09x = 1,532,936.28
  5. Step 5: Solve for x
    x = 1,532,936.28/1,389.09
  6. Step 6: Final answer
    x = 1,103.55

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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.