Its true because you have to subtract in the long version so do you want me to show it to you?
In 10 months Lisa will have paid the same amount as Kelly, but in month 11 she will have paid more.
3 is less than 5, so rounded to the nearest ten is 360.
6 is greater than 5, so rounded to the nearest hundred, our answer is 400.
The answer to this is 720000
