By selling an article for ₹ 96, a man gains as much percent as its cost price. Find the cost price of the article.

A trader brought a number of articles for ₹ 900, five were damaged and he sold each of the rest at ₹ 2 more than what he paid for it. If on the whole he gains ₹ 80, find the number of articles brought.

A sum of ₹ 54000 is invested partly in shares paying 6% dividend at 40% premium and partly in 5% shares at 25% premium. If the nominal value of one share in each company is ₹ 100 and the total income of the man is ₹ 2,240, find the money invested in the second company.

Solve and graph the solution set of :

(i) 2x - 9 < 7 and 3x + 9 ≤ 25; x ∈ R

(ii) 3x - 2 > 19 or 3 - 2x ≥ 7; x ∈ R