Current location - Training Enrollment Network - Mathematics courses - People's education press seventh grade math book p 106~ 108. Answer quickly! ! ! By the way, I'm still chasing points
People's education press seventh grade math book p 106~ 108. Answer quickly! ! ! By the way, I'm still chasing points
1: X cubic meters as the desktop.

20X*4=400( 12-X)

X=5( 12-X)

X= 10

4: (x-1) * (1/5+1/7.5+1/5) =1.

(X- 1)*8/ 15= 1

X- 1