# Exam average

Average of marks that have on the certificates students of 8.A class in mathematics is exactly 2.45. If we did not add 1 and 3 of sutdents Michael and Alena, who arrived a month ago, it would average exactly 2.5.

Determine how many students have class 8.A.

Determine how many students have class 8.A.

**Result****Leave us a comment of example and its solution (i.e. if it is still somewhat unclear...):**

**Showing 0 comments:**

**Be the first to comment!**

#### To solve this example are needed these knowledge from mathematics:

## Next similar examples:

- Family parcels

In father will he divided the land so that the older son had three bigger part than younger son. Later elder son gave 2.5 ha field to younger and they had both the same. Determine the area of family parcel. - Two numbers

We have two numbers. Their sum is 140. One-fifth of the first number is equal to half the second number. Determine those unknown numbers. - 13 tickets

A short and long sightseeing tour is possible at the castle. Ticket for a short sightseeing circuit costs CZK 60, for a long touring circuit costs CZK 100. So far, 13 tickets have been sold for 1140 CZK. How much did you pay for tickets for a short tour? - Three figures - numbers

The sum of three numbers, if each is 10% larger than the previous one, is 662. Determine the figures. - Belgium vs Italy

Belgium played a match with Italy and Belgium win by 2 goals. The match fell a total 6 goals. Determine the number of goals scored by Belgium and by Italy. - Football match 4

In a football match with the Italy lost 3 goals with Germans. Totally fell 5 goals in the match. Determine the number of goals of Italy and Germany. - Dining room

The dining room has 11 tables (six and eight seats). In total there are 78 seats in the dining room. How many are six-and eight-seat tables? - Theatro

Theatrical performance was attended by 480 spectators. Women were in the audience 40 more than men and children 60 less than half of adult spectators. How many men, women and children attended a theater performance? - Football season

Dalibor and Adam together scored 97 goals in the season. Adam scored 9 goals more than Dalibor. How many goals scored each? - Viju

viju has 40 chickens and rabbits. If in all there are 90 legs. How many rabbits are there with viju?? - ATC camp

The owner of the campsite offers 79 places in 22 cabins. How many of them are triple and quadruple? - Rabbits 3

Viju has 40 chickens and rabbits. If in all there are 90 legs. How many rabbits are there with Viju? - Mushrooms

Eva and Jane collected 114 mushrooms together. Eve found twice as much as Jane. How many mushrooms found each of them? - Trees

Along the road were planted 250 trees of two types. Cherry for 60 CZK apiece and apple 50 CZK apiece. The entire plantation cost 12,800 CZK. How many was cherries and apples? - Equations

Solve following system of equations: 6(x+7)+4(y-5)=12 2(x+y)-3(-2x+4y)=-44 - Linear system

Solve this linear system (two linear equations with two unknowns): x+y =36 19x+22y=720 - Substitution

solve equations by substitution: x+y= 11 y=5x-25