Tham Khảo :
a) A = m x 2 + p x 2
= 50 x 2 + 20 x 2
= 100 + 40
= 140
B = ( m + n + p ) x 2
= ( 50 + 30 + 20 ) x 2
= 100 x 2
= 200
b) M = a - ( b + c )
= 2000 - ( 500 + 200 )
= 2000 - 700
= 1300
N = a - b - c
= 2000 - 500 - 200
= 1500 - 200
= 1300
a: \(A=B=2\left(m+n+p\right)=2\cdot100=200\)
b: \(M=N=a-b-c=2000-700=1300\)