{This afternoon, an outdoor temperature had a reading of|On a cold February afternoon, the temperature outside was} `abs( X )` degrees below zero. {By evening, the temperature had dropped by|In the evening, you take a quick look at the thermometer, and see that the temperature had dropped by} `Y` degrees.

What was the temperature in the evening?

`Z` degrees

degrees below zero is the same as `abs( X )`

.`X`^{\circ}

Since the temperature dropped by

, subtract this amount from the afternoon temperature.`Y`^{\circ}

`X`^{\circ} - `Y`^{\circ} = `Z`^{\circ}

The temperature in the evening was

.`Z`^{\circ}

{When `person( 1 )` went outside to go sledding in the morning|As `person( 1 )` prepared for `his( 1 )` daily sledding practice}, `he( 1 )` {looked at the thermometer and saw|heard on the radio} that the temperature was `abs( X )` degrees below zero. {After sledding for `plural( randRange( 1, 8 ), "hour" )`,|After a long day of sledding `he( 1 )` saw that} the temperature was now `Z` degrees.

By how many degrees had the temperature increased?

`Y` degrees

degrees below zero is the same as `abs( X )`

.`X`^{\circ}

Change in temperature = final temperature - initial temperature

Change in temperature = `Z`^{\circ} - (`X`^{\circ}) = `Z`^{\circ} - `X`^{\circ} = `Y`^{\circ}

The temperature had increased by

.`Y`^{\circ}

`person( 1 )` was scuba diving `X` meters below sea level when `he( 1 )` spotted a beautiful fish below. {From a distance, the fish looked to be about `randRange( 25, 35 )` cm wide. |}{To take a proper photograph|To see the fish up close}, `person( 1 )` dove `Y` meters until `he( 1 )` was level with the fish, staring into its eyes.

Where was the fish relative to sea level?

`Z` meters

`person( 1 )` was initially

meters below sea level, which can be written as a negative number, `X``-`

meters.`X`

`person( 1 )` dove down

meters, so we can subtract that distance from `Y``person( 1 )`’s initial level to find out where the fish is.

Fish’s position relative to sea level `=-`

`X`\text{ meters} - `Y`\text{ meters} = `Z`\text{ meters}

A spinner dolphin jumped from `X` meters below sea level and flipped through the air at `Y` meters above sea level. {The jump itself took about 1.`randRange( 1, 9 )` seconds.|}

How many meters did the dolphin travel to reach the highest point of the jump?

`Z` meters

The dolphin was initially `X` meters below sea level, which can be written as a negative number, -`X` meters.

Distance the dolphin jumped = final position - initial position

`Y`\text{ meters} - (-`X`\text{ meters}) = `Y`\text{ meters} + `X`\text{ meters} = `Z`\text{ meters}

`person( 1 )` received a loan of $`commafy( X )` from the bank to start a baseball camp. `person( 1 )` used the loan to rent baseball bats, mitts, and baseballs for the summer, and to pay the coaches’ salaries. Over the course of the summer, `N` campers attended `person( 1 )`’s baseball camp, and each camper paid a fee of $`COST` to attend. `person( 1 )` used all of the money from the campers’ fees to start paying back the loan.

At the end of the summer what was `person( 1 )`'s net worth, assuming `he( 1 )` had no other assets or liabilities?

`person( 1 )` started out the summer with `$`

of debt, which can be represented as a negative number, `commafy( X )``-$`

.`commafy( X )`

Amount of money `person( 1 )` earned from campers = `N` \times $`COST`=$`commafy( Y )`

debt + earnings = `person( 1 )`'s account balance

`-$`

`commafy( X )` + $`commafy( Y )` = -$`commafy( Z )`