What is the estimate using the break apart strategy of 731 + 207?

Noor brought 21 sheets of stickers. she gave 1/3 of a sheet to each of the 45 students at recess. she wants to give teachers 1 1/2 sheets each.

240 seventh graders and two-thirds of the students participate in after-school activities how many students participate in after-school activities

Ahyperbola centered at the origin has a vertex at (-6,0) and a focus at (10,0)