If you put in z to the equation

you get

and that equals 9 so the answer is B. 9
First, you add the two parts of the ratio together. 8+5=13. Then you do 390 divided by 13 which is 30. After this, you multiply 30 by each side to get the ratio to be equal. 30x8=240, and 30x5=150. This can now be put into the ratio 240:150. As you said it was in the ratio adults to children, it must stay in that order. The part of the ratio for children is 150.
<em>The answer to your question is 150. You can double-check your answer by adding up the two parts again. 240=150=390 so you can be assured that your answer is truly correct. Thank you for uploading this question. I hope my explanation was helpful enough for you
</em>
<em><u>PencilandPaper21</u></em>
Answer:

Step-by-step explanation:
The sum of the interior angles of a triangle add up to
. Therefore, an equiangular triangle will have each of its angles equal to
. We can then set up the following equation:
.
Answer:
it is simple those are linear equation.
u multiply 2 to 5 then find its lcm u'll get the answer.