90000 is the significant figures
It's the same amount each month, for a year. So:
total money ÷ times money was taken out= how much has been taken out.
$600÷12=50
First you make them fractions that have the same denominator. 12 can be the denominator, because 6 5/12 already has that denominator and to get 2 2/3 to have a denominator of 12, you multiply the numerator and denominator by 4 (3•4=12, but you have to do the same thing to the top and bottom of the fraction). You then have the equation
6 5/12- 2 8/12. Since you cant subtract 8/12 from 5/12, you turn the numbers into improper fractions, which would be
77/12 - 32/12. You subtract them and get 45/12. You then have to simplify it again, 12 can go into 45, 3 times and you would have 3 and 9/12. 9/12 can be simplified down to 3/4. So the answer would be 3 3/4.