It’s important to learn math in school, or you may end up being mocked by the Huffington Post.

Read: Make financial literacy lessons fun

Readers in customer service gave Huff Post photos of receipts from clients who were either too lazy or incapable of adding a tip to their tab and calculating the total.

Check them out here.

Sometimes, it’s good to run through the basics. Make sure your new clients are comfortable with basic investment concepts.

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