6 650 + 9 543 + 3 250 – 9 900
= (6 650 + 3 250) + 9 542 – 9 900
= 9 900 + 9 542 – 9 900
= 9 900 – 9 900 + 9 542
= 0 + 9 542 = 9 542
6 650 + 9 543 + 3 250 – 9 900
= (6650 + 3250) + 9542 – 9900
= 9900 + 9542 – 9900
= 9900 – 9900 + 9542
= 0 + 9542 = 9542