The first spike technique-summation method. This skill comes in handy if the words "* *" and "total * *" appear in the topic.

The second spike technique-divisible method. If the words "divisible", "average" and "every" appear in the title, they can all be used! On the other hand, when data: multiple, fraction, percentage and proportion appear in the title, it can also be divisible.

The third spike skill-proportional multiple feature. When "percentage" or "fraction" appears in the topic, or the information in the topic gives the proportional multiple relationship between the two quantities, we can try to solve it with the technique of proportional multiple feature.