Question

write the set in Roster form and write cardinal number. B={x:x ∈ N is a multiple of 4, x <30} ​

Answer 1

$Given \: B = \{ x:x\in N \: is \: a \: multiple \: of \: 4 , x \lt 30 \}$

$\underline {\pink{ Roster \: form \: of \: Set \: B : }}$

$B = \{ 4,8,12,16,20,24,28 \}$

$\blue{ Cordinal \: number \:of \: B }$

$n(B) = number \: of \: elements \: in \: B$

$= 7$

Therefore.,

$\green {B = \{ 4,8,12,16,20,24,28 \}}$

$\red{ Cordinal \: number \:of \: B } \green {=7}$

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