python-intro/exercises/ex02_variables_assignment.ipynb

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    "# Exercise 2: Variables and assignment"
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    "## Aim: Introduce Python variables and perform calculations with them."
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    "### Issues covered:\n",
    "- Creating variables\n",
    "- Simple arithmetic\n",
    "- Using `print` to display variables\n",
    "- Looking at strings"
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    "## 1. Let's create some variables and print their values"
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    "Create a variable called `course` and assign it the value `\"python\"`."
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    "Create a variable called `rating` and assign it an integer value of your choice."
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    "Print these variables to your screen using the `print` function."
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   "source": [
    "Try printing the values without using the `print` function. "
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    "_Note: This method works in notebooks, however in a script you will need to use `print`._"
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   "source": [
    "## 2. Let's use Pythagoras' Theorem to calculate the length of the hypotenuse of a right-angled triangle where the other sides have lengths 3 and 4."
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    "Create variables called `b` and `c` and assign them the values of the sides with known lengths."
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    "We can use variables in calculations - try writing a mathematical expression to calculate the length of the hypotenuse."
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    "_Hint: Remember Pythagoras' Theorem: $a^2$ = $b^2$ + $c^2$_"
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    "If you haven't already, create a variable `a` and set its value to the result of the calculation."
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    "## 3. Let's extract some data from strings."
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    "Return only `Data Analysis` from the string. _Hint: The D in Data is the 26th character_."
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