Home / 1,391.20-1,919.84-801.92

Finding the Fourth Proportional to 1,391.20, 1,919.84 and 801.92

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Solution

The fourth proportional to 1,391.20, 1,919.84 and 801.92 is: 1,106.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,391.20 : 1,919.84 = 801.92 : x
  2. Step 2: Convert to fraction form
    1,391.20/1,919.84 = 801.92/x
  3. Step 3: Cross multiply
    1,391.20x = 1,919.84 × 801.92
  4. Step 4: Simplify right side
    1,391.20x = 1,539,558.09
  5. Step 5: Solve for x
    x = 1,539,558.09/1,391.20
  6. Step 6: Final answer
    x = 1,106.64

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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.