10)

11)

12)

13) (your answer is incorrect)

14) (your answer is incorrect)

15)

16)
-expression to represent this situation

Answer: In 1 group 57 students
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P.S. Hello from Russia :^)
Answer:
81 adult tickets
Step-by-step explanation:
Step 1:
Set up a system of equations
Since the adult tickets and student tickets add to 243, we can do

and the student tickets sold were 2x the adult tickets, we can do

We can replace s in the first equation adding to 243 with 2a

Step 2:
Solve for a. We can divide both sides by 3.

Therefore, there were 81 adult tickets sold.
Step 3:
We can check our work! Since we learned earlier the student tickets are 2x adult tickets, we can multiply 81 by 2 and add that to 81 to see if it equals 243!

And...

So, 81 must be the answer!
Answer:
79.6
Step-by-step explanation:
4 3/5+15÷1/5
23/5+15÷1/5
4.6+15÷0.2
4.6+75
79.6
The two numbers are 41 & 37.
The way to solve this is by setting up an equation. We know that 2 numbers are going to equal 78, so here would be the general equation (let x represent the number we don't know):
(x) + (x + 4) = 78
Now, we need to simplify it (combine like terms):
2x + 4 = 78
Then you can solve it like any other equation. Subtract 4 on both sides:
2x = 74
Divide by 2 on both sides:
x = 37.
So, now you know one number is equal to 37 and that the other is 37 + 4.
That's how you get 37 & 41.
Answer:
x+ 1
d+4
y+3
Step-by-step explanation: