Here is the ultimate strategy:

1. Go to Prealgebra.
2. Select the topic "Basic Statistics".
3. Start using the strategy:

Strat:
Here are the rules:
1. The most important rule: DO NOT GET REVIEW PROBLEMS WRONG. Why? Because if you get one wrong and it happens to be in Algebra too, then your Algebra rating is screwed.
2. Rule for Power grinding: Get 20 problems wrong when first starting out. Then, start repeating this pattern: Solve power questions right, once you see a streak of 5 questions right, get 5 questions wrong unless they have power. Then get the power and do 6 questions wrong.
For how many questions right you get, get the same number wrong.
3. Once you're power level 25, do this for resilience: Get every accuracy problem wrong on the first try, then get them right on the second try. Same for power. Get problems with no accuracy or power wrong.
4. Once you are resilience level 25, the final grind is upon you: Accuracy. This one is the hardest one.
Get problems wrong and right in this pattern: (x's are wrongs, o's are rights): xxxxxoooxxoooxxxoooxxoooxxxoo and repeat that pattern over and over again.