Question

Each 7th grader brings $5 for charity, while each 8th grader brings in $8. The total collected is $1380. There are 10 more 8th graders than 7th graders. How many students are in each grade?

Answer 1

Answer:

7th graders- 100 students

8th graders- 110 students

Step-by-step explanation:

Let the number of 8th graders be represented by x and 7th graders be represented by y

Equation based on number

There difference between 8th and 7th graders is 10 hence equation becomes

x-y=10

Equation based on contribution

While x contribute each $8 and y contribute each $5, the total contribution is $1380 hence the equation becomes

8x+5y=1380

Combining equations

Having the two simultaneous equations which are

x-y=10

8x+5y=1380

Solving the equations.

5x-5y=50

8x+5y=1380

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13x=1430

x=1430/13=110

Therefore, 8th graders are 110. Since the 8th graders were 10 more than 7th graders, the 7th graders will be 110-10=100 students