Write an equation system based on the problem
x stands for the bat, and y stands for the baseball
"A toy baseball and bat cost $1.50 together" could be written as:
∴ x + y = 1.5
"The bat costs $1.00 more than the baseball" could be written as:
∴ x = y + 1
Solve the equation system by substitution method. Plug x as y + 1 into the first equation
x + y = 1.5
y + 1 + y = 1.5
2y + 1 = 1.5
2y = 1.5 - 1
2y = 0.5
y = 0.5/2
y = 0.25
The baseball costs $0.25