ruby bought $18 worth of donuts and cookies. each donut costs $1 and each cookie costs $1.50. she bought a total of 15 donuts and cookies all together. graphically solve a system of equations in order to determine the number of donuts, x, and the the number of cookies, y, that ruby bought.

16. you're planning to buy a boat, a motor, and some miscellaneous boating equipment. the boat costs $325, the motor costs $225, and the equipment costs $79. if you've saved $438 toward these purchases, how much more do you need to save? a. $181 b. $281 c. $291 d. $191

How to find the exponential function y=ca^x, with points (1,2) and (2,1)

Christine wong has asked dave and mike to her move into a new apartment on sunday morning. she has asked them both, in case one of them does not show up. from past experience, christine knows that there is a 40% chance that dave will not show up and a 30% chance that mik a. what is the probability that both dave and mike will show up? (round your answer to 2 decimal places.) b. what is the probability that at least one of them will show up? c. what is the probability that neither dave nor mike will show up? (round your answer to 2 decimal places.)e will not show up. dave and mike do not know each other and their decisions can be assumed to be independent.