School trip graders

Sixth, seventh, and eighth graders took part in the school trip. Sixth graders were 5 more than seventh graders, and eighth graders were 3 less than sixth graders. How many sixth graders were on the trip if there were 73 students in total?

Final Answer:

a =  27

Step-by-step explanation:

$$\begin{gathered} a+b+c=73 \\ a=5+b \\ c=a-3 \\ a+(a-5)+(a-3)=73 \\ 3a=81 \\ a=\frac{81}{3}=27 \\ a=27 \\ \text{ Verifying Solution: } \\ b=a-5=27-5=22 \\ c=a-3=27-3=24 \\ s=a+b+c=27+22+24=73 \end{gathered}$$

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