Răspuns
Explicație pas cu pas:
a. 10/n=5/3
5n=3x10
n=(3x10)/5
n=30/5 n=6
b. 15/(n+3)=3/7
3(n+3)=15x7
3n+9=105
3n=105-9
3n=96
n=96/3 n=32
c. (n-4)/(n+8)=1/7
(n+8)=7(n-4)
n-8=7n-28
7n-n=28+8
6n=36 n=36/6 n=6
d. (4n-3)=(3n+6)/5
5(4n-3)=3(3n+6)
20n-15=9n+18
20n-9n=18+15
11n=33 n=33/11=3 n=3