There are 5 red pens, 3 blue pens, and 2 green pens in a box. kelvin takes a pen randomly from the box and gives it to samuel. kelvin then takes another pen randomly and replace it back into the box (10 pens remaining). work out the probability that both pens are the same pen.

Evaluate the dot product of (3,-1) and (1,5)

Alicia puts $400 in a bank account. each year the account earns 5% simple interest. how much money will be in her bank account in six months?

Type the correct answer in the box. consider the system of linear equations below. rewrite one of the two equations above in the form ax + by = c, where a, b, and c are constants, so that the sum of the new equation and the unchanged equation from the original system results in an equation in one variable.