Question

va rog ajutati-ma :(Calculati si scrieti rezultatul in forma de fractie ordinara: 

a) 2,52 * 0,(3);

b) 5/7 * 2,8; 

c) 5/9 * 7,2; 

d) 4,(3) + 4,(2); 

e) 9/38 * 4,(2);

f) 1,2(1) * 100/90.

Answer 1

a) 2,52 x 0,(3)=252/100x3/9=252/100x1/3=252/300=simplif cu 2=126/150=simplif cu 2=63/75=simplif.cu 3=21/25

b) 5/7 x 2,8=5/7x28/10=140/70=14/7=2=2/1

c) 5/9 *x7,2=5/9x72/10=360/90=36/9=4=4/1

d) 4,(3) + 4,(2)=(43-4)/9+(42-4)/9=99/9+38/9=(39+38)/9=77/9

e) 9/38 x 4,(2)=9/38x(42-4)/9=9/38x38/9=se simplif cu 9=38/38=1=1/1

f) 1,2(1) *x100/90=(121-12)/90x100/90=109/90x100/90=109/9x1/9=109/81