एक बैग में केवल चार रंगों की गेंदें हैं। इसमें 12 को छोड़कर सभी नीली गेंदें, 21 को छोड़कर सभी काली गेंदें, 20 को छोड़कर सभी लाल गेंदें और 19 को छोड़कर सभी हरी गेंदें हैं। बैग में कुल कितनी गेंदें हैं?

Some friends decided to go on a picnic and the amount fixed for expenditure was ₹ 768. Due to the non-arrival of four friends, each participating friend had to bear an additional amount of ₹ 16. How many friends participated in the picnic?

From a certain number of apples, a man sells half the number of apples plus 1 to the first customer, sells 13 of the remaining apples plus 1 to the second customer, and 15 of the remaining apples plus 1 to the third customer. He then finds that he has 3 apples left. How many apples did he have initially?