number patterns
posted by mona .
joshua is raising fruit flies for a science project.at the begining of the first day,he had 4 fruit flies,his fruit flies double in number each day.how many fruit flies does he have at the end of three days

beginning of first day 4
end of first day 8
end of second day  16
.
.
mmmhhh. 
12

argggg!!
don't the numbers double?? 
Mona,
The numbers double. As Reiny said, the first day there's 4, the next day 8, the next day 16. Add those three numbers together for the total amount. 
1st day = 4
2nd day = 8( double of 4)
3rd day = 16 ( double of 8) 
4 +4=8 +8=16 answer