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We can convert octal to decimal in the same way we converted binary to decimal. For example, we use the powers of eight just as we did in the lookup table to convert 0o456 to decimal:

power | 2 | 1 | 0 |
---|---|---|---|

value | 64 | 8 | 1 |

number | 4 | 5 | 6 |

product | 256 | 40 | 6 |

Multiply out the number and product rows; for example, 4 x 64 = 256. Add the bottom row to get our decimal result:

`$4 \cdot 64 + 5 \cdot 8 + 1 \cdot 6$`

`$256 + 40 + 6 = 302$`

Let’s try another one with 0o5376:

power | 3 | 2 | 1 | 0 |
---|---|---|---|---|

value | 512 | 64 | 8 | 1 |

number | 5 | 3 | 7 | 6 |

product | 2560 | 192 | 56 | 6 |

We add up the bottom row to get our decimal number:

`$2560 + 192 + 56 + 6 = 2814$`

### Instructions

**1.**

In octal, we are looking at powers of what base number?

Set the value to `checkpoint_1`

in the code editor.

**2.**

What is 0o3671 in decimal?

Set the value to `checkpoint_2`

in the code editor.

**3.**

What is 0o1570 in decimal?

Set the value to `checkpoint_3`

in the code editor.

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