Make 2/3 into 8/12 then subtract 1/12 and you get 7/12
f = twenty bill
f = fifty bill
f + t = 18(gave total 18 bills) and 50f + 20t = 450 ($450 cash a check)
Answer is B.
f + t = 18 ; 50f + 20t = 450
300 * 6 = 1800
Chelsea's family traveled a total of 1800 miles in 6 days.
wish I could help but don't now whatn you are saying