Home / 1,389.76-1,917.64-800.28

Finding the Fourth Proportional to 1,389.76, 1,917.64 and 800.28

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Solution

The fourth proportional to 1,389.76, 1,917.64 and 800.28 is: 1,104.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,389.76 : 1,917.64 = 800.28 : x
  2. Step 2: Convert to fraction form
    1,389.76/1,917.64 = 800.28/x
  3. Step 3: Cross multiply
    1,389.76x = 1,917.64 × 800.28
  4. Step 4: Simplify right side
    1,389.76x = 1,534,648.94
  5. Step 5: Solve for x
    x = 1,534,648.94/1,389.76
  6. Step 6: Final answer
    x = 1,104.25

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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.