Home / 1,280.66-1,921.39-613.83

Finding the Fourth Proportional to 1,280.66, 1,921.39 and 613.83

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Solution

The fourth proportional to 1,280.66, 1,921.39 and 613.83 is: 920.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.66 : 1,921.39 = 613.83 : x
  2. Step 2: Convert to fraction form
    1,280.66/1,921.39 = 613.83/x
  3. Step 3: Cross multiply
    1,280.66x = 1,921.39 × 613.83
  4. Step 4: Simplify right side
    1,280.66x = 1,179,401.69
  5. Step 5: Solve for x
    x = 1,179,401.69/1,280.66
  6. Step 6: Final answer
    x = 920.93

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.