Review the basics
Be comfortable with fractions, percentages, ratios, inflation rates, power laws, basic geometry concepts, etc. Take a few sample tests to practice and then review any concept you do not fully master
You are often allowed to use a calculator - make sure you know how to use it!
Bring your own, and learn how to use it to save valuable time during the interviews
Questions are designed to confuse you
Some questions can be tricky. It's a multiple choices, and some questions may have solutions that are very close to the correct answer, or include some solutions that represent the most common calculation mistakes that can be made. For example mixing units (kg with g), confusing different different charts on a graph, etc. So make sure that you are 100% confident in your answer and have a rapid double check before submitting it.
Attention to detail is key
Pay attention to units, scales, etc. Make sure you spend some time scanning the data before rushing into calculations
Answer questions randomly if you run out of time
It's better to try to answer a question than not answering at all - at least by answering you get a chance to get it right.
- previously published at AskIvy.net