Question

В зале 8 рядов стульев,по 9 стульев в каждом ряду. В зал привели учеников двух классов, по 30 учеников в каждом. Хватит ли для них стульев?Если окажутся лишние стулья, то сколько их будет?

Answer 1

8*9=72 стула
72- (30*2) = 12 лишних

Answer 2

8*9=72 cтула всего
30*2=60 учеников
72-60=12 стуьев лишних

Answer 3

Calculation of the Number of Chairs Needed

To determine if there are enough chairs for the students, we need to calculate the total number of chairs required and compare it to the number of chairs available.

Given: - There are 8 rows of chairs. - Each row contains 9 chairs. - There are 2 classes, with 30 students in each class.

To find the total number of chairs needed, we can multiply the number of rows by the number of chairs in each row and then multiply that by the number of classes.

Total number of chairs needed = (Number of rows) x (Number of chairs in each row) x (Number of classes)

Substituting the given values: Total number of chairs needed = 8 x 9 x 2 = 144

Therefore, a total of 144 chairs are needed for the students.

Calculation of Excess Chairs

If there are any excess chairs, we can calculate the number of excess chairs by subtracting the total number of chairs needed from the total number of chairs available.

Given: - There are 8 rows of chairs. - Each row contains 9 chairs.

To find the total number of chairs available, we can multiply the number of rows by the number of chairs in each row.

Total number of chairs available = (Number of rows) x (Number of chairs in each row)

Substituting the given values: Total number of chairs available = 8 x 9 = 72

To calculate the number of excess chairs, we subtract the total number of chairs needed from the total number of chairs available.

Number of excess chairs = Total number of chairs available - Total number of chairs needed

Substituting the values: Number of excess chairs = 72 - 144 = -72

Since the result is negative (-72), it means that there are not enough chairs for all the students. There is a shortage of 72 chairs.

Therefore, there are no excess chairs; instead, there is a shortage of 72 chairs.

Summary: - A total of 144 chairs are needed for the students. - There is a shortage of 72 chairs.