Jo has a gerbil and a german shepard. the shepherd eats 14 times as much food as the gerbil. altogether, they eat 225 ounces of food does the german shepherd eat per week?

First, lets represent
the gerbil eats 1 food unit
the german shepard eats 14 times of gerbil or 14 food units
together they eat 225 oz per week so
gerbil=1food unit
german shepard=14 food unit
add them together
gerbil+german shepard=15 food unit
15 food unit=225 oz
divide both sides by 15
1 food unit=15 oz
we want to find 14 food unit
15 oz times 14=210 oz
the german shepherd eats 210 oz per week