Răspuns :
1. 20 m...7 h/zi...22 zile
1 m...7 h/zi...22*7=154 zile
14 m...7 h/zi...154:14=11 zile
14 m...x h/zi... 55 zile = 11*5 zile
x=7/5 h/zi = 1,4 h/zi
2. 27 m...9 h/zi...15 zile
x m...3 h/zi...45 zile
1 m...9 h/zi...27*15=405 zile
1 m...1 h/zi...405*9=3645 zile
1 m...3 h/zi...3645:3=1215 zile
x=1215:45 m =27 m
3. 9 kg... L=27 m si l=3 dm
x kg... L=54 m si l=8 dm
9 kg... S=(270*3) dm^2= 810 dm^2
x kg... S=(540*8) dm^2= 4320 dm^2
1 kg... S=810:9 dm^2= 90 dm^2
x=4320:90 kg= 48 kg
4. 21 kg... L=70 m si l=3 dm
90 kg... L=x dm si l=10 dm
21 kg... S=(700*3) dm^2= 2100 dm^2
1 kg... S=2100:21 dm^2 = 100 dm^2
90 kg... S=(x*10) dm^2= 9000 dm^2
x=9000:10 dm = 900 dm
5. 72 r...48 hl...5 h
x r... 54 hl... 9 h
1 r...48 hl... 5*72=360 h
1 r...1 hl... 360*48=17280 h
1 r...54 hl... 17280:54=320 h
x=320:9 r= ~36 r
1 m...7 h/zi...22*7=154 zile
14 m...7 h/zi...154:14=11 zile
14 m...x h/zi... 55 zile = 11*5 zile
x=7/5 h/zi = 1,4 h/zi
2. 27 m...9 h/zi...15 zile
x m...3 h/zi...45 zile
1 m...9 h/zi...27*15=405 zile
1 m...1 h/zi...405*9=3645 zile
1 m...3 h/zi...3645:3=1215 zile
x=1215:45 m =27 m
3. 9 kg... L=27 m si l=3 dm
x kg... L=54 m si l=8 dm
9 kg... S=(270*3) dm^2= 810 dm^2
x kg... S=(540*8) dm^2= 4320 dm^2
1 kg... S=810:9 dm^2= 90 dm^2
x=4320:90 kg= 48 kg
4. 21 kg... L=70 m si l=3 dm
90 kg... L=x dm si l=10 dm
21 kg... S=(700*3) dm^2= 2100 dm^2
1 kg... S=2100:21 dm^2 = 100 dm^2
90 kg... S=(x*10) dm^2= 9000 dm^2
x=9000:10 dm = 900 dm
5. 72 r...48 hl...5 h
x r... 54 hl... 9 h
1 r...48 hl... 5*72=360 h
1 r...1 hl... 360*48=17280 h
1 r...54 hl... 17280:54=320 h
x=320:9 r= ~36 r