Juan is riding his bicycle. he rides at a speed of 6.4 kilometers per hour for 4 hours. for how many kilometers does he ride?

27 is what percent of 108? 27 is % of 108

When x = 3 and y = 5, by how much does the value of 3x2 – 2y exceed the value of 2x2 – 3y ?

Sam opened a money-market account that pays 3% simple interest. he started the account with $7,000 and made no further deposits. when he closed the account, he had earned $420 in interest. how long did he keep his account open?