Home / 1,280.12-1,766.43-720.61

Finding the Fourth Proportional to 1,280.12, 1,766.43 and 720.61

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Solution

The fourth proportional to 1,280.12, 1,766.43 and 720.61 is: 994.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.12 : 1,766.43 = 720.61 : x
  2. Step 2: Convert to fraction form
    1,280.12/1,766.43 = 720.61/x
  3. Step 3: Cross multiply
    1,280.12x = 1,766.43 × 720.61
  4. Step 4: Simplify right side
    1,280.12x = 1,272,902.71
  5. Step 5: Solve for x
    x = 1,272,902.71/1,280.12
  6. Step 6: Final answer
    x = 994.37

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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.