Tính ra trước đã nhé:
A= [ 0,8.7+ [tex]\dpi{120} (0,8)^{2}[/tex] ] (1,25.7 - [tex]\dpi{120} \frac{4}{5}[/tex].1,25 ) + 31,64
A= [0,8.(7+0,8) ] . [ 1,25.(7- [tex]\dpi{120} \frac{4}{5}[/tex] ) ] +31,64
A= 6,24+7,75+31,64
A= 80
B=[tex]\dpi{120} \frac{(1,09-0,29).\frac{5}{4}}{(18,9-16,65).\frac{8}{9}}[/tex]
B=[tex]\dpi{120} \frac{\frac{4}{5}.\frac{5}{4}}{\frac{9}{4}.\frac{8}{9}}[/tex]
B= [tex]\dpi{120} \frac{1}{2}[/tex]
A gấp B là:
80: [tex]\dpi{120} \frac{1}{2}[/tex]=160 (lần)