To add -4 and 5, draw the starting number on a number line and count to the right when adding numbers. What is the difference in temperature between a desert at 40 °C and a mountain top at -2 °C? \(40 ...

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Have you ever tried to add or subtract fractions that have different denominators? It’s tricky, right? Join Ms. Susanna Post in this lesson to learn how to solve these types of challenging problems!