SSC JE Civil Engineering 29-Oct-2020 Shift 1 Paper

Numbers = 3, 5, 8, 11, 14, 18, 22, 10, 9 and x.
Arithmetic Mean = 12
Formula:
Arithmetic mean = Sum of the Numbers ÷ Number of terms
Calculation:
Sum of the given numbers = 3 + 5 + 8 + 11 + 14 + 18 + 22 + 10 + 9 + x = 100 + x
Number of terms = 10
Substituting the values in the equation,
12 = (100 + x) ÷ 10
12 × 10 = 100 + x
120 = 100 + x
x = 120 - 100
x = 20.
Hence, the correct answer is "20".