BECE Mathematics 2018 Paper

Factors are numbers which can go into the number whose factors is being determined.Factors of 36 are numbers that can go into 36Factors of $36, P=\{1,2,3, \{4\}, 6,9, \{1,2\}, 18, \{3,6\}\}$Multiples of 4 less than $40, Q=\{\{4\}, 8, \{1 2\}, 16,20,24,28,32, \{3 6\}\}$Intersection $\cap$ means element you can find in both sets$P \cap Q = \lbrace 4,12,36 \rbrace$If a set contains ' $n$ ' elements, then the number of subsets of the set is $2^n$.The number of elements in $P \cap Q$ is 3 , hence the number of subsets could be calculated as:Subsets $=2^3=2 \times 2 \times 2=4 \times 2=8$