engineering recuitment HAL Management & Design Trainee Mock Test 2023 Engineering Mathematics Probability and Statistics
If x and y are deviation from mean x̅ and y̅ respectively and if r = 0.5, ∑xy = 120, σy = 8 and ∑x2 = 90, what is the value of 'n' ?
1
8
2
15
3
12
4
10