Real-Life Math -- Solution
1. How much do you make from repairs and product sales every month? What is your monthly profit after expenses?
You know that 20 percent of what you charge for repairs goes to cover the cost of materials. That means you keep 80 percent.
$3,200 worth of repairs x 0.80 = $2,560
You currently make $2,560 a month from repairs.
You know that 30 percent of what you charge from your products goes into your pocket.
$1,700 worth of products x 0.30 = $510
You currently make $510 from product sales.
$2,560 + $510 = $3,070
In total, you make $3,070 (before other expenses).
$3,070 profit - $600 rent - $300 other expenses = $2,170
Your current monthly profit after all expenses is $2,170.
2. How much will you make from repairs and product sales every month after the price increase and move? What will be your monthly profit after expenses?
$3,200 worth of repairs x 0.85 = $2,720
You will make $2,720 a month from repairs.
$1,700 worth of products x 0.40 = $680
You will make $680 a month from product sales.
$2,720 + $680 = $3,400
In total, you will make $3,400 (before other expenses).
$3,400 profit - $800 rent - $300 other expenses = $2,300
After the price increases and the move, you will make a monthly profit after all expenses of $2,300 a month.
Many shoemakers and repairers have their own shops, so they use math for accounting and keeping track of inventory.
"You definitely have to budget supplies and accounts payable," says shoe repairer Mike Elain. "You have to be able to keep a daily track of your repairs, minus your cost of materials."
Math is also used when shortening belts or adjusting the sizes of shoes. It's mostly measuring. With experience, the calculations are all done in your head.