18 is what percent of 36?

Abike shop sells you a bicycle for $63 and a helmet for $21. the total cost is 150% of what the shop spent originally. how much did the shop spend originally? how much profit did the bike shop earn by selling the bicycle and helmet to you ?

Lena reflected this figure across the x-axis. she writes the vertices of the image as a'(−2, 8), b'(−5, 6), c'(−8, 8), d'(−4, 2).

Kendra had twice as much money as kareem. kendra later spent $8 and kareem earned $6. by then, the two had the same amount of money. how much money did each have originally?