Question:
Observe the tables given below and in each case find whether x and y are inversely proportional:
(i) 
Solution:
(i) Clearly, $6 \times 9 \neq 10 \times 15 \neq 14 \times 21 \neq 16 \times 24$
Therefore, $x$ and $y$ are not inversely proportional.
(ii) Clearly, $5 \times 18=9 \times 10=15 \times 6=3 \times 30=45 \times 2=90=($ consant $)$
Therefore, $x$ and $y$ are inversely proportional.
(iii) Clearly, $9 \times 4=3 \times 12=36 \times 1=36$, while $6 \times 9=54$
i. e., $9 \times 4=3 \times 12=36 \times 1 \neq 6 \times 9$
Therefore, $x$ and $y$ are not inversely proportional.