The way to do this is:(Look at picture)
It will take her 30 minutes to type it because if you take 2100 and divide it by 350 you’ll get 6,so that how many times it fix’s into it,then do 6x5 then you get your answer
Let, the number of month = m
Equation would be: 4800 - 400m = 2000
In order to solve for number of months,
400m = 4800 - 2000
400m = 2800
m = 2800 / 400
m = 7
So, after 7 months, account balance will be $2000
Hope this helps!
18/5 = x/100
1800 = 5x
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5 5
360 = x
You can use proportion to solve your equation to figure out the x value so you have corresponding ratios