Home / 1,389.56-1,917.65-800.09

Finding the Fourth Proportional to 1,389.56, 1,917.65 and 800.09

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Solution

The fourth proportional to 1,389.56, 1,917.65 and 800.09 is: 1,104.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,389.56 : 1,917.65 = 800.09 : x
  2. Step 2: Convert to fraction form
    1,389.56/1,917.65 = 800.09/x
  3. Step 3: Cross multiply
    1,389.56x = 1,917.65 × 800.09
  4. Step 4: Simplify right side
    1,389.56x = 1,534,292.59
  5. Step 5: Solve for x
    x = 1,534,292.59/1,389.56
  6. Step 6: Final answer
    x = 1,104.16

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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.