Agroup of students calculated their average score at a spelling bee. they realized that if one of them scored 9 more points, their average score would be 81 points. if one of them scored 3 points less, their average score would be 78 points. how many students were in the group?

There are 4 students in the group.

Step-by-step explanation:

Let the number of students in the group be n

If one of them scored 9 more points , their average score would be 81 points.

So, our equation (1) will be

Similarly,

If one of them scored 3 points less, their average score would be 78 points.

So, our equation (2) will be

So, from equation (1) and (2) we get:

Hence, there are 4 students in the group.

the figures below are made out of circles, semicircles, quarter … find the area and the perimeter of each figure and give your answers as a completely simplified exact value in terms of π (no approximations). remember that we'll also have to cut whatever areas we get in half, since we're only dealing

step-by-step explanation:

the 4th choice is the correct one

step-by-step explanation: