math
posted by Anonymous .
if i have 5 days to sell 200 tickets by friday how many tickets do i have to sell the first day if i sell ten less then the previous day

something is missing here.

like what

how many tickets do i have to sell the first day if i sell ten less then the previous day
that makes no sense. There is no previous day to the first day. 
Monday you sold x tickets
Tuesday you sold x10
wedn ... x20
thu ... x30
frid ...x40
x + x10 + x20 + x30 + x40 = 200
5x  100 = 200
x = 60
On the first day you had to sell 60 tickets.
check:
What is 60+50+40+30+20 ?