Scientific Understanding

**How do you do multiplication on a calculator?**

The first thing we need to understand for chemistry is how different math signs can be written. I will skip addition and subtraction because those are very straight forward and not as commonly used throughout the material you will need for the chemistry class. That leaves multiplication and division. In this section I will tackle how multiplication can appear in different ways and how to use your calculator to solve multiplication problems. In the next section on division I will answer questions about division.

Some people can get confused if I use the (x) symbol for multiplication because they have been taught in math that “x” can represent a variable. Therefore, on most of this website I will try not to use the “x” for multiplication. Instead I prefer to use the (*) symbol or parentheses to represent multiplication.

**Examples**: These are the ways multiplication can be written. I demonstrate how these examples are put into your calculator with these two different links. **VIDEO Multiplication examples with a regular calculator. VIDEO Multiplication with a graphing calculator.**

5 times 3 = | 15 |

6 x 2 = | 12 |

4 * 5 = | 20 |

7(3) = | 21 |

(8)(9) = | 72 |

In text I tend to write multiplication like below

5 | 7 = | 35 |

3 | 9 = | 27 |

20 * 4 | 8 * 6 = | 3840 |

**PRACTICE PROBLEMS**: Tell me what the answers are to these problems.

12 times 3 = | 36 |

50 x 4 = | 200 |

33 * 2 = | 66 |

6(0) = | 0 |

(10)8 = | 80 |

4(5)2(3) = | 120 |

3 | 2 = | 6 |

4 | 6 = | 24 |

12 * 5 | 9 * 7 = | 3780 |