Home / 1,280.49-1,766.91-720.89

Finding the Fourth Proportional to 1,280.49, 1,766.91 and 720.89

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Solution

The fourth proportional to 1,280.49, 1,766.91 and 720.89 is: 994.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.49 : 1,766.91 = 720.89 : x
  2. Step 2: Convert to fraction form
    1,280.49/1,766.91 = 720.89/x
  3. Step 3: Cross multiply
    1,280.49x = 1,766.91 × 720.89
  4. Step 4: Simplify right side
    1,280.49x = 1,273,747.75
  5. Step 5: Solve for x
    x = 1,273,747.75/1,280.49
  6. Step 6: Final answer
    x = 994.73

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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.