I can't seem to figure out how to do this? Can someone please not just give me the answer but also explain it to me?

Daniel bought a computer game for $25 and later sold it to thomas for a 40% profit. how much did daniel sell the computer game for?

Look at arnold's attempt to solve the equation for b: 3b = 12 b = 3 · 12 b = 36 describe the mistake that arnold made.

Meghan has created a diagram of her city with her house, school, store, and gym identified. a. how far is it from the gym to the store? b. meghan also wants to walk to get some exercise, rather than going to the gym. she decides to walk along arc ab. how far will she walk? round to 3 decimal places.