a,47-[(45×16-25×12):14]
=47-[(720-300):14]
=47-[420:14]
=47-30
=17
b,50-[(20-8):2+34]
=50-[12:2+34]
=50-[6+34]
=50-40
=10
c,100-[60:(5^2-15)]
=100-[60÷(25-15)]
=100-[60÷10]
=100-6
=94
d,50-[(50-8×5)÷2+3]
=50-[(50-40)÷2+3]
=50-[10÷2+3]
=50-[5+3]
=50-8
=42
e,10-[(64-48).5+(8×10+8)]÷28
=10-[16.5+(80+8)]÷28
=10-[80+88]÷28
=10-168÷28
=10-6
=4
( bạn tự viết đầu bài nhé)
a,47-[(45×16-25×12):14]
=47-[(720-300):14]
=47-[420:14]
=47-30
=17
b,50-[(20-8):2+34]
=50-[12:2+34]
=50-[6+34]
=50-40
=10
c,100-[60:(5^2-15)]
=100-[60÷(25-15)]
=100-[60÷10]
=100-6
=94
d,50-[(50-8×5)÷2+3]
=50-[(50-40)÷2+3]
=50-[10÷2+3]
=50-[5+3]
=50-8
=42
e,10-[(64-48).5+(8×10+8)]÷28
=10-[16.5+(80+8)]÷28
=10-[80+88]÷28
=10-168÷28
=10-6
=4