Write an equation to solve

Keisha bought a used bike for $12 more than half its original price. She paid $72. What was the original price?

Julia chooses a card at random from her set of cards. what is the probability that the card is labeled cat or hamster?

Adepartment store purchases screen-printed t-shirts at a cost of $5 per shirt. they mark up the price 150% (making the selling price 250% of the store's purchase price) and put them on the sales floor. every month that a t-shirt doesn't sell, the store reduces the selling price by 25%.

The measure of one angle of an octagon is two times smaller that of the other seven angles. what is the measure of each angle?