Home / 1,280.11-1,766.64-720.63

Finding the Fourth Proportional to 1,280.11, 1,766.64 and 720.63

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Solution

The fourth proportional to 1,280.11, 1,766.64 and 720.63 is: 994.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.11 : 1,766.64 = 720.63 : x
  2. Step 2: Convert to fraction form
    1,280.11/1,766.64 = 720.63/x
  3. Step 3: Cross multiply
    1,280.11x = 1,766.64 × 720.63
  4. Step 4: Simplify right side
    1,280.11x = 1,273,081.35
  5. Step 5: Solve for x
    x = 1,273,081.35/1,280.11
  6. Step 6: Final answer
    x = 994.51

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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.