Marks at school

There are 30 students in the class. Five students in the class had a mark three triple at the end of the math certificate, and the other students had a mark of one or two. The average mark in all students' mathematics in the class at the end of the year was 1.9. Find out how many students in the class had a mark one on the year-end math certificate.

Correct answer:

x =  8

Step-by-step explanation:

1•x + 5•3+ (30-5-x)•2= 1.9•30

x = 8

Our simple equation calculator calculates it.

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