Answer: Lucas had $7
Step-by-step explanation:
Let x represent the amount of money that Lucas had initially.
Let y represent the weight of each type of oat that he bought.
Lucas bought a certain weight of oats for his horse at a unit price of .20 per pound. The total cost left him with one extra dollar. This means that
x - 0.2y = 1 - - - - - - - - - - - -- - 1
He wanted to buy the same weight for enriched oats instead, but at .30 per pound he was short 2 dollars. This means that
x - 0.3y = - 2- - - - - - - - - - - -- - 1
Subtracting equation 1 from equation 2, it becomes
0.1y = 3
y = 3/0.1
y = 30
Substituting y = 30 into equation 1, it becomes
x - 0.2 × 30 = 1
x - 6 = 1
x = 1 + 6
x = 7
