# Classroom

In a classroom are 30 students, boys are four times more than girls. How many boys are in the class?

Result

x =  24

#### Solution:

x+y=30
x = 4y

x+y = 30
x-4y = 0

x = 24
y = 6

Calculated by our linear equations calculator.

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

Be the first to comment!

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

Do you have a linear equation or system of equations and looking for its solution? Or do you have quadratic equation?

## Next similar examples:

1. Katy
Kate paid for the package on delivery of four meters textile 688 CZK. What is the price of one meter textile when shipping and handling amounted to 48 CZK?
2. Bakers
Baker Martin baked 5 times more cakes than Dennis. How many cakes baked Dennis if Martin bake 25 cakes?
3. School marks
Boris has a total of 22 marks. Ones have 3 times less than threes. There are two twos. How many has ones and threes?
4. Sparrow ball
On the sparrows ball were males and females. There were 170 sparrows. Males was 20 more than females. How many sparrow female was at a ball?
5. Salary
Mr. Vesely got for work 874 CZK (Czech Republic Koruna). Mr. Jaros got twice less than Mr. Vesely. How much CZK got Mr. Jaros?
6. Mom and daughter
Mom is 30 years older than the daughter. What is the age difference between them in 35 years?
7. Snacks
The school attends 344 pupils. Half of them take snacks. 13 pupils who took snacks did not attend school. How many snacks left?
8. Bus
On the 4-th stop take on 56 and take off 38 passengers. How many were added (write as positive number) or shrunk (write as negative number) the count of passengers?
9. Cars
Johnny has 370 cars. Peter twice less. How many cars have Peter?
10. Bus 2
On the 6-th stop 44 passengers take off from bus. Overall, the 6-th stop 13 passengers were added. How many passengers take on 6-th stop?
11. Book
Louise read from their favorite book for three days 18 pages. Every day read the same number of pages. How many pages she read every day?
12. Euro
I have 1 euro. How much will I have when you spend it on?
13. Grandmother
Children's grandmother bought two identical toy cars and a doll. Total paid 492 Kč. The doll was 150 Kč. How much money cost 1 toy car?
14. Flour
2 kg of flour costs 100 CZK. How much does it cost half a kilogram?
15. Unknown number xyz
Find the number that its triple is 24. Solve by equation.
16. Dividing by five and ten
Number 5040 divide by the number 5 and by number 10: a = 5040: 5 b = 5040: 10
17. Breeder
Seven hens breeder has supplied 350 eggs. How long can deliver, if each of its chickens can withstand at least 5 eggs for week?