Plz help ASAP and good explanation thank you

If 20% of a number is 35, what is 50% of that number?

Aschool allots ? 1500 to spend on a trip to the theatre. theatre tickets have a regular cost of ? 55 each and are on offer for 1 5 off. a train ticket for the day will cost ? 12 each. if 2 teachers and the maximum number of students attend, how much money will the school have left over?

Intro biblioteca sunt 462 de carti cu 198 mai putine enciclipedii si cu 47 mai multe dictionare decat enciclopedii cate enciclopedii sunt in biblioteca