Home / 2,121.58-3,198.63-1,978.64

Finding the Fourth Proportional to 2,121.58, 3,198.63 and 1,978.64

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Solution

The fourth proportional to 2,121.58, 3,198.63 and 1,978.64 is: 2,983.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,121.58 : 3,198.63 = 1,978.64 : x
  2. Step 2: Convert to fraction form
    2,121.58/3,198.63 = 1,978.64/x
  3. Step 3: Cross multiply
    2,121.58x = 3,198.63 × 1,978.64
  4. Step 4: Simplify right side
    2,121.58x = 6,328,958.68
  5. Step 5: Solve for x
    x = 6,328,958.68/2,121.58
  6. Step 6: Final answer
    x = 2,983.14

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.