Home / 1,280.18-1,766.66-720.65

Finding the Fourth Proportional to 1,280.18, 1,766.66 and 720.65

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Solution

The fourth proportional to 1,280.18, 1,766.66 and 720.65 is: 994.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.18 : 1,766.66 = 720.65 : x
  2. Step 2: Convert to fraction form
    1,280.18/1,766.66 = 720.65/x
  3. Step 3: Cross multiply
    1,280.18x = 1,766.66 × 720.65
  4. Step 4: Simplify right side
    1,280.18x = 1,273,144.34
  5. Step 5: Solve for x
    x = 1,273,144.34/1,280.18
  6. Step 6: Final answer
    x = 994.50

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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.