I like using Unit Percentages here.
We know 45% is $1100 which means 90% is $2200 but we need to know 100%.
Again we know 45% is $1100 and I’ll use the unit percent of 5%. To get from 45 to 5 we divide by 9 so we’ll divide $1100 by 9 and find out the value of each 5% worth.
Another way is to set up a proportion. A proportion in this case is x/100 = is/of.
It’s like asking $1100 is 45% of what number.
To set this proportion up you’d have 45/100 = $1100/x. Cross multiply (diagonally) and you get 45x = $110000. Divide by 45 and you get ~$2444.44