You want to buy a bouquet of yellow roses and daises, and you have $15 to spend. A daisy costs $.90 and a rose is $1.50. You have 5 daises. Write and solve an equation for the number of roses r you can buy

Due to bad planning, two of the local schools have their annual plays on the same weekend. while 457 people attend one, and 372 attend the other, only 104 people were able to attend both. how many people went to at least one play?