Idiom: It's raining cats and dogs
Meaning: It's raining very heavily

We use this idiom to say that it is raining VERY heavily. It does not actually mean that cats and dogs are falling out the sky!

Examples:

• The weather was horrible on Saturday. It was raining cats and dogs all day.
• It's really awful weather outside. It's windy and is raining cats and dogs.

Example 1: 105 x 105

1. Determine the difference between 105 and 100, which is 5.
2. Add this number to 105, which is 105 + 5 = 110
3. Square the number in Step 1, that is 5^2 = 25
4. The answer is 11025

This works for all numbers up to 150 but is more useful if the number is close to 100. 

It also works for numbers smaller then 100 but in that case you simply have to subtract the difference to 100 from your number.

Example 2: 96 x 96

1. Determine the difference between 96 and 100, which is -4.
2. Add this number to 96, which is 96 + (-4) = 92
3. Square the number in Step 1, that is (-4)^2 = 16
4. The answer is 9216

The following video is giving you some more examples and also shows what happens for larger distances.