In a school of 2000 students, the ratio of teachers to students is 3:80, Some teachers join the school and the ratio changes to 1:20.
Find the number of teachers who joined the school,

Determine the number of girls in a math class with 87 boys if there are 25 girls for every 75 boys

Clara schumann is buying bagels for her coworkers, she buys a dozen bagels priced at $5.49 a dozen. the bakery's cost for making the bagels is $2.25 per dozen. what is the markup rate based on selling price on a dozen bagels?

Daniel expanded the expression as shown below -2(-8x-4y+3/4)=-10x-8y-11/4 what errors did he make? check all that apply