Given, Jason had an amount of $d in the piggy bank.
After one week, Jason doubled the amount in the piggy bank.
So, after one week the amount in the piggy bank = $ = $(2d)
Another week later, Jason added $20 in the piggy bank.
So after another week, the total amount in the piggy bank = $
Given, that time the piggy bank had $50 in it.
So we can write the equation as,
To find the value of d, we will move 20 to the right side by subtracting it from both sides. We will get,
Now to find d, we will move 2 to the right side by dividing it to both sides. We will get,
We have got the required answer.
The value of d = $15.