There are few rows in the garden. If 4 plants are planted in each row, then 3 rows are left unoccupied. However, if 3 plants are planted in each row then 3 plants are left. How many plants are there?

Let
rr = number of rows in the garden
nn = total number of plants If 4 plants are planted in each row, then 3 rows are left unoccupied. That means only r−3r−3 rows are used.
Each of these rows has 4 plants, so: n=4×(r−3)n=4×(r−3) If 3 plants are planted in each row then 3 plants are left. That means all rr rows are used, but 3 plants remain unplanted: n=3r+3n=3r+3 4(r−3)=3r+34(r−3)=3r+34r−12=3r+34r−12=3r+34r−3r=3+124r−3r=3+12r=15r=15 n=4(15−3)=4×12=48n=4(15−3)=4×12=48 Check with the other equation: n=3×15+3=45+3=48n=3×15+3=45+3=48