Question

 1.Daca 1.2/x = 1 intreg si 1/3/2,5 ,atunci x = ....

Alta problema: 
2.Daca 1,25/a=b/0,3,calculeaza 100 aXb.

Answer 1

 1) 1 intreg 1/3/2,5

2,5= 2 intregi 5/10= 2 intregi 1/2= 5/2

1 intreg 1/3/5/2= 1 intreg 1/3 * 2/5= 1 intreg 2/15= 17/2

1 2/x=  (x+2)/x

(x+2)/x= 17/2

17x =2(x+2)

17x =2x +4

17x-2x=4

15x=4

x= 4/15

2) 1, 25= 1 intreg 25/100= 1 intreg 1/4= 5/4

0,3=3/10

5/4/a= b/3/10

5/4 * 1/a= b * 10/3

5/4a=10b/3

10b=15/4a

b=15/4a/10

b=15/4a * 1/10

b=3/4a * 1/2

b= 4/8a

100a x b = 100 * a * 4/8a= 25 * 4/2= 25 *2=50