Home / 1,290.52-1,920.38-1,286.20

Finding the Fourth Proportional to 1,290.52, 1,920.38 and 1,286.20

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Solution

The fourth proportional to 1,290.52, 1,920.38 and 1,286.20 is: 1,913.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,290.52 : 1,920.38 = 1,286.20 : x
  2. Step 2: Convert to fraction form
    1,290.52/1,920.38 = 1,286.20/x
  3. Step 3: Cross multiply
    1,290.52x = 1,920.38 × 1,286.20
  4. Step 4: Simplify right side
    1,290.52x = 2,469,992.76
  5. Step 5: Solve for x
    x = 2,469,992.76/1,290.52
  6. Step 6: Final answer
    x = 1,913.95

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.