Gloria, Tina, and Kelly went to an office supply store. Gloria bought 5 pencils, 7 markers, and 8 erasers. Her total was $19.00.
Tina spent $21.00 buying 7 pencils, 5 markers, and 8 erasers. Kelly bought 4 pencils, 8 markers, and 7 erasers for $17.75. What is the cost of each item?
Looking at the graph, we'll notice that there is a local maximum at x=0 and it looks similar on both sides of the y axis, therefore making it symmetric around the y axis given the options
You have to divide 300 with 15, the answer to that is: 300/15=20. However, if she starts saving this week (counting as a first), she will have enough money in 19 weeks after the first week, she needs 20 weeks to save the money.