Hi!
We know the prices of one pencil, one eraser and one pencil sharpener, which are $0.45, $0.30 and $0.30, respectively. Given that, we will find the cost of 3 pencils, 2 erasers and 1 pencil sharpener like this:
3 * 0.45 + 2 * 0.30 + 1 * 0.30 = 1.35 + 0.60 + 0.30 = 2.25
The cost of 3 pencils, 2 erasers and 1 pencil sharpener is $2.25.
Hope this helps!