ANSWER
45 weeks
Step-by-step explanation
We have that the cost of the PlayStation 5 after tax is $600.
Let the number of weeks it will take to be able to afford it be x.
This means that the sum of the Christmas gift and the allowance saved for x weeks must be equal to $600.
Therefore:
150 + (10 * x) = 600
150 + 10x = 600
Collect like terms:
10x = 600 - 150
10x = 450
Divide through by 10:
x = 450 / 10
x = 45 weeks
It will take 45 weeks for you to be able to afford the PlayStation 5.