Home / 1,390.80-1,919.26-801.46

Finding the Fourth Proportional to 1,390.80, 1,919.26 and 801.46

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Solution

The fourth proportional to 1,390.80, 1,919.26 and 801.46 is: 1,105.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,390.80 : 1,919.26 = 801.46 : x
  2. Step 2: Convert to fraction form
    1,390.80/1,919.26 = 801.46/x
  3. Step 3: Cross multiply
    1,390.80x = 1,919.26 × 801.46
  4. Step 4: Simplify right side
    1,390.80x = 1,538,210.12
  5. Step 5: Solve for x
    x = 1,538,210.12/1,390.80
  6. Step 6: Final answer
    x = 1,105.99

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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.