Toni needs a total of $600 to buy a cell phone. she has already saved $350. if she saves $40 a week from her earning what is the least number of weeks she must work to have enough money to buy the cell phone?

Acertain population of bacteria demonstrates exponential growth doubles in size every 4 days. how long will it take the population to triple in size?

Trent wants to buy 2 packs of trading cards for 3 dollars each. the trading card packs that trent normally buys tend to come in packs of 6, 10, 12, or 15 cards. after selecting 2 packs, trent found that the first pack of cards cost 25 cents per card, and the second pack cost 30 cents per card. trent uses this information to write the equations below in order to compare c, the number of cards in each pack.

Which of the following pair(s) of circles have las a common external tangent? select all that apply. a and b a and c b and c