**Challenge:** will all values of `||variables:x||`

and `||variables:y||`

make
sense with this formula?
If not, what constraints can we place on `||variables:x||`

and `||variables:y||`

to ensure that Tom a number of oranges that makes sense?

# Problem Set: Math

This section contains a number of selected problems for the Math section.

It is recommended that you review the problems, and complete a few before moving on to the next section.

## Problem #1: Apples to Oranges

Use variables in JavaScript to store the number of fruit each person has.

- Randy has 5 apples
- Chris has 12 lemons
- Anna has 3 more apples than Randy
- Janet has 2 less lemons than Chris
- Tom has a number of oranges equal to the number of lemons Janet has minus the number of apples Anna has

## Problem #2: Difficult Math

Math can be hard, but computers are good at it. Use JavaScript to compute the following:

Equation | Equation | ||
---|---|---|---|

(a) |
`15,391` + `4,273` = |
(g) |
`87,849,383` ÷ `7,481` = |

(b) |
`12,589` + `2,531` = |
(h) |
`72,395,941` ÷ `16,063` = |

(c) |
`13,577` - `8,039` = |
(i) |
`9,439` - `4,831` + `8,237` = |

(d) |
`3,307` - `1,103` = |
(j) |
`4,567` - `3,761` × `2,281` = |

(e) |
`10,177` × `13,159` = |
(k) |
`3,337` × `8,633` ÷ `4,183` = |

(f) |
`3,089` × `4,111` = |
(l) |
`10,181` + `112,911,179` ÷ `12,049` = |

## Problem #3: Apples to Oranges II

Use variables in JavaScript to store the number of fruit each person has.

- Randy has
`||variables:x||`

apples - Chris has
`||variables:y||`

lemons - Anna has 3 more apples than Randy
- Janet has 2 less lemons than Chris
- Tom has a number of oranges equal to the number of lemons Janet has minus the number of apples Anna has

This equation for different values of `||variables:x||`

and `||variables:y||`

.
Start with `x = 5`

and `y = 12`

and see if you get the same results as Problem #1.

## Problem #4: Perfect PEMDAS Practice

For the following expressions, add parentheses to the equations to make the statements true:

Equation | Equation | ||
---|---|---|---|

(a) |
`9` - `5` - `3` = `7` |
(g) |
`18` / `2` + `16` = `1` |

(b) |
`13` - `3` - `7` = `17` |
(h) |
`12` - `6` / `3` = `2` |

(c) |
`12` - `7` + `1` = `4` |
(i) |
`18` / `3` + `3` = `3` |

(d) |
`6` + `2` * `12` = `96` |
(j) |
`18` / `1` + `5` - `2` = `1` |

(e) |
`11` - `2` * `5` = `45` |
(k) |
`2` * `5` + `20` / `2` = `25` |

(f) |
`16` + `13` * `3` = `87` |
(l) |
`6` + `15` / `3` + `1` = `8` |

## Problem #5: Birthday Algorithm

Implement the Birthday Algorithm from CS Intro 1 in JavaScript:

Start with the variables `||variables:month||`

and `||variables:day||`

the both store numbers.
Assign these values to a person’s birthday.

For each step below, modify a variable called `||variables:output||`

that **also** stores a number.

- Start with the number 7 (
`let output: number = 7`

) - Multiply by month the person was born (number 1 - 12)
- Subtract 1
- Multiply by 13
- Add 5
- Subtract 2
- Add the day the person was born (number 1 - 31)
- Multiply by 11
- Subtract day the person was born (number 1 - 31)
- Subtract month the person was born (number 1 - 12)
- Divide by 5
- Add 22
- Divide by 200

When finished, `||game:game.splash||`

`||variables:output||`

to the screen.