a, 4.25-3.(24-9)=100-3.(24-9)=77.15=1155

b,7+6.(1\4)=13.1\4=13\4

c,32.7+32=224+32=256

câu 2

(x-15):5+22=24

(x-15):5=24-22

(x-15):5=2

(x-15)=5.2

(x-15)=10

x=10+15

x=25

|x+7|=15-(-4)

|x+7|=19

x=19-7

x=12

(x-1\2):1\3+5\7=68\7

(x-1\2):1\3=68\7-5\7

(x-1\2):1\3=9

(x-1\2)=9.1\3

(x-1\2)=3

x=3+1\2

x=7\2