If you have an 81 average overall in algebra and get a 90 on a test what is your new average? Help Asap

Fredrick designed an experiment in which he spun a spinner 20 times and recorded the results of each spin

Nick has box brads. he uses 4 brads for the first project. nick let’s b represent the original number of brads and finds that for the second project, the number of brads he uses is 8 more than half the difference of b and 4. write an expression to represent the number of brads he uses for the second project.

Acomputer store bought a program at a cost of $10 and sold it for $13. find the percent markup