What kind of mathematics are you learning?
Answer:
24
Step-by-step explanation:
Step-by-step explanation:





D=# of tickets sold at the door
a=# of tickets sold in advance
3a+5d=2630
d=a+30
3a+5(a+30)=2630
8a+150=2630
8a=2480
a=310
d=340
310 tickets were sold in advance and 340 tickets were sold at the door.
120 has the same value as 12 tens