10 (above) sigma notation i=11 (below) to the right is (7i-3) , how do i solve this or enter it into the calculator for later?

If 1 is divided by the sum of y& 4.the result is equal to 3 divided by 4, find the value of m

Standard deviation of 19,29,21,22,23

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?