If it took you (one person) 3 days to build a doghouse, then it should take 2 people to build it in half the time. So all we have to do is split 3 days in 2.
3/2 = 1.5
So it would take 1 1/2 days or 36 hours for 2 people to complete the doghouse.
Looking at the two black dots
5 bulbs cost $9
Divide total cost by number of bulbs bought:
9 / 5 = $1.80 per bulb.
10 bulbs cost $18
Divide total cost by number of bulbs bought:
18 / 10 = $1.80 per bulb
The cost for one bulb is $1.80
