方程式唔識做!

(a/2-a/5)*5=24

(5a/10-2a/10)*5=24

(3a/10)*5=24

15a/10=24

15a=240

a=240/15

a=16

(a/2-a/5)*5=24
a/2-a/5=24/5
5a/10-2a/10=4 4/5
3a/10=4 5/4
3a=4 5/4*10
a=48/3
a=16

(a/2-a/5)*5=24

2.5a-a=24

1.5a=24

a=24/1.5

a=16

(a/2-a/5)*5=24

5a/2-5a/5=24

25a/10-10a/10=240/10

25a-10a=240

15a=240

a=16

(a/2-a/5)*5 = 24

=> a/2 - a/5 = 24/5

=> 5a/10 - 2a/10 = 24/5

=> 3a/10 = 24/5

=> (3/10) a = (24/5)

=> a = (24/5) / (3/10) = (24/5) * (10/3) = 8 / 2 = 4

明白就好la~~!

5[5(a/2)-2(a/5)]=24
5(5a/10-2a/10)=24
5(3a/10)=24
3a/2=24
3a=48
a=16

the ans is 400
step : (a/2-a/5)*5=24
(3a/10)=120
a=400