A carpenter can build 1 doghouse in 1 day. How many doghouses can 12 carpenters build in 20 days?

In the polynomial below, what number should replace the question mark to produce a difference of squares? x2 + ? x - 36

At $1.32 million, they closed last month percent above what they paid in 2007." how much did they pay in 2007?

Last month, a 770 g box of cereal was sold at a grocery store for $3.10. however, this month, the cereal manufacturer launched the same cereal in a 640 g box, which is being sold at $2.50. what is the percent change in the unit price?