x= # students who got lower grades
2x+3= # students with grade A
STEP 1:
Add the two sets above equal to 24.
x + (2x + 3)= 24
combine like terms
3x + 3= 24
subtract 3 from both sides
3x= 21
divide both sides by 3
x= 7 (# students lower than A)
STEP 2:
substitute x value from step 1 to find # grade A students
=2x + 3
=2(7) + 3
=14 + 3
=17 (# grade A students)
CHECK:
x + (2x + 3)= 24
7 + 2(7) + 3= 24
7 + 14 + 3= 24
24= 24
ANSWER: There were 17 students with grade A.
Hope this helps! :)
