How can finding the lcm and gcf me understand multiple and divide

The following frequency table relates the weekly sales of bicycles at a given store over a 42-week period.value01234567frequency367108521(a) in how many weeks were at least 2 bikes sold? (b) in how many weeks were at least 5 bikes sold? (c) in how many weeks were an even number of bikes sold?

At a sale this week, a desk is being sold for $213. this is a 29% discount from the original price. what is the original price?

For f(x)=2x+3 and g(x)=x^2- 8 find (f+g) (x)