VERIFIED WAEC Gce obj and Theory Runz 2017 below:
No. 5
∑fx = 0 + 3 + 10 + 33 + 40 + 70
∑fx = 156
∑f = 7 + 3 + 5 + 11 + 10 + 14
∑f = 50
Mean = ∑fx / ∑f
Mean = 156 / 50
Mean = 3.12
Interquartile range
Inter-quartile Range = Q3 - Q1
Where:
Q3 = (3(N + 1) / 4)th item
Q1 = ((N + 1) / 4)th item
N = Sum of the frequencies
Arranging the set of data in ascending order we have:
0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3,
3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
5, 5
N = 7 + 3 + 5 + 11 + 10 + 14
N = 50
Q3 = (3(50 + 1) / 4)th item
Q3 = (3(51) / 4)th item
Q3 = (153 / 4)th item
Q3 = 38.25th item
Q3 = 5
Q1 = ((6 + 1) / 4)th item
Q1 = (51 / 4)th item
Q1 = 12.75th item
Q1 = 2
Inter-quartile Range = 5 - 2
Inter-quartile Range = 3
____
1a) 1+_/72
________
_/2
Where_/2=1.414
_____
1 +_/36×2
____________
_/2
1+6_/2
_________
_/2
Recall_/2 =1.1414
1+6(1.1414)
__________________
1.1414
=6. 7072
6) M = ns + pr / s + r
ns + pr = M(s + r)
ns + pr = Ms + Mr
Pr - Mr = Ms - ns
r(p-m) = s(m-n)
r(p-m) / (p-m) = s(m-n) / (p-m)
r= s(m-n) / (p-m)
. : m = 15, n = 10, s = 2.5, p = 18
r = 2.5(15 - 10) / 18 - 15
r = 2.5(5) / 3
r = 12.5 / 3
r = 4.166
r = 4.17
