TRICK TO SUBSTRACT NUMBER EASILY
This is an easy trick To subtract a large number from 1,000 subtract all but the last number from 9, then subtract the last number from 10 1000 -547 step1: subtract 5 from 9 = 4 step2: subtract 4 from 9 = 5 step3: subtract 7 from 10 = 3 answer: 453