Home / 1,286.18-1,787.24-1,272.80

Finding the Fourth Proportional to 1,286.18, 1,787.24 and 1,272.80

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Solution

The fourth proportional to 1,286.18, 1,787.24 and 1,272.80 is: 1,768.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,286.18 : 1,787.24 = 1,272.80 : x
  2. Step 2: Convert to fraction form
    1,286.18/1,787.24 = 1,272.80/x
  3. Step 3: Cross multiply
    1,286.18x = 1,787.24 × 1,272.80
  4. Step 4: Simplify right side
    1,286.18x = 2,274,799.07
  5. Step 5: Solve for x
    x = 2,274,799.07/1,286.18
  6. Step 6: Final answer
    x = 1,768.65

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.