Question

Last year you mowed grass or shoveled snow
for 12 households. You charged $200 a season
to mow a yard and $180 a season to shovel
snow. You earned $2260 last year.
How many households did you mow?

Answer 1

Let s= yards snow shoveled; Let m= yards mowed. For two unknowns, you need two equations to solve.

So

s+m=12

$200m+$180s= $2,260

Reagrange the first equation.

So

s=12-m

Plug this equation into the second one.

$200m+($180)(12-m)=$2,260

$200m-$180m+ $2,160=$2,260

$20m=$2,260-$2,160

m=5

So he mowed 5 lawns.