Question 1096894
<br>Often, the algebra we do to solve a problem like this is exactly what we could do to solve the problem using logical analysis.<br>
Compare the solution below using logical analysis to the very good algebraic solution provided by the other tutor:<br>
(1) Have 5 of the girls step out of the room.
(2) That leaves equal numbers of boys and girls, with a total of 30 students.
(3) So there are 15 boys and 15 girls.
(4) Bring the 5 girls back into the room.
(5) There are now 15 boys and 20 girls.<br>
Do you see that this is EXACTLY what the formal algebra does?<br>
I am not saying that you should use logical analysis instead of formal algebra.  Quite the opposite -- I am saying that you should understand WHY the solution using formal algebra makes sense.