1) Number of plants in a * * * *:
48000/(0.2*0.2)= 1200000 (strain)
Because A is twice as much as B, so
Answer: 1200000/3*2=800000 (strain)
B:1200000/3 *1= 400000 (strain)
(2) Let commodity A be RMB X and commodity B be RMB 500-X..
X*70%+(500-X)90%=386
0.7X+450-0.9X=386
0.2X=450-386
X=320
500-320= 180
A commodity 320 yuan, b commodity 180 yuan.
(3) Suppose: there are x boys and x-/kloc-0 girls.
X=(X- 1- 1)*2
X=(X-2)*2
X=2X-4
2X-X=4
X=4
There are four boys and three girls.