"The recommended daily calcium intake for a 20-year-old is 1,000 milligrams (mg). One cup of milk contains 299 mg of calcium and one cup of juice contains 261 mg of calcium. Which of the following inequalities represents the possible number of cups of milk m and cups of juice j a 20-year-old could drink in a day to meet or exceed the recommended daily calcium intake from these drinks alone?" What is a way to start this question in order to make it easier to solve?
I would first write out the amounts they provide you with in short hand so it is easier to see: "total calcium intake = 1000", "calcium in milk = 299", "calcium in juice = 261". Then you know if you drink m cups of milk, you would consume 299m mg of calcium, and 261 j from the juice. Using these facts, you are easily able to arrive at the answer 299m + 261j >= 1000.
If solving an equation with multiple steps, where do you start?
Go backwards in terms of order of operations in order to isolate the variable you are solving for. For example, you would add constant numbers before dividing/multiplying, or taking square roots of the variable you wish to solve for.
How does a merge sort work?
You first have two halves of the data sorted individually. Then to combine the two halves, you look at the first value in each one and compare them to each other. Whichever one is the smaller (or preferred) value, pick that one and add it to the result. Keep going throughout both data sets until no values are left.