Question

Roger bought two plots of land for $120000. He sold the first plot and profited 15%. He sold the second plot and lost 10%. His total profit was $5500. How much did he pay for each plot?

Answer 1

he paid $70000 and $ 50000

Answer 2

x + y = 120000
0.15x - 0.10y = 5500

Multiply both sides of bottom by 100 to remove decimals

x + y = 120000
15x - 10y = 550000

Multiply both sides of top by 10

10x + 10y = 1200000
15x - 10y = 550000

Add the two

25x = 1750000
x = 70000
He paid $70,000 for the property that made a profit, and paid $50,000 for the property that lost value.