hard math problem help is needed?

Jared earns money by making gift baskets for Father's Day. He does one filled with fishing supplies and one with a sports fan theme. He makes a profit of $9.00 on the fishing supply basket and a profit of $12.50 on the sports fan basket. He only has time to make 100 baskets and needs to earn at least $1,000 to cover his summer activities. Which solution stifies the system of inequalities? a) 73 fishing baskets and 27 sports fan baskets b) 75 fishing baskets and 25 sports fan baskets c) 70 fishing baskets and 30 sports fan baskets d) 72 fishing baskets and 28 sports fan baskets
--------------------
Let F be the number of fishing baskets made by Jared Let S be the number of sports fan baskets made by Jared There are 2 inequalities that have to be satisfied: "He only has time to make 100 baskets," meaning: (1) F + S ? 100 and "needs to earn at least $1,000," meaning: (2) 9F + 12.5S ? 1000 You'll find that options A, B, C, and D all satisfy the first inequality, so we really just need to determine the number of fishing and sports fan baskets Jared has to make to earn at least $1,000. (A) F = 73, and S = 27 => 9F + 12.5S = 9(73) + 12.5(27) = 994.5 < 1000 In other words, option A is not good enough to earn $1,000 (B) F = 75, and S = 25 => 9F + 12.5S = 9(75) + 12.5(25) = 987.5 < 1000 In other words, option B is not good enough to earn $1,000 (C) F = 70, and S = 30 => 9F + 12.5S = 9(70) + 12.5(30) = 1005 > 1000 In other words, Jared can earn at least $1,000 with option C (D) F = 72, and S = 28 => 9F + 12.5S = 9(72) + 12.5(28) = 998 < 1000 In other words, option D is not good enough to earn $1,000 Therefore, to satisfy the system of inequalities, Jared should go with option C (i.e. to make 70 fishing baskets and 30 sports fan baskets).
Source