[tex]a) \frac{a}{2} + 2a= \frac{a}{2}+ \frac{2a}{1}= \frac{a}{2}+ \frac{2*2a}{2}= \frac{a}{2}+ \frac{4a}{2}= \frac{5a}{2}=\frac{5}{2}a=2,5a\\\\[/tex]
b) 4b- b/3= 4b/1- b/3=3*4b/3-b/3=12b/3-b/3=12b-b/3= 11/3 b
c) n/2+ n/8 = 4n/8+ n/8= 4n+n/8= 5n/8= 5/8 n
d) 3x/2 + x/4 = 2*3x/2*2 + x/4=6x/4 + x/4= 7x/4=7/4 x
e) y/7- y/8 = 8*y/8*7- 7*y/7*8= 8y/56-7y/56=y/56=1/56y
f) 2c/3 - 1/2c = 2*2c/2*3- c/2=4c/6-c/2= 4c/6- 3*c/3*2= 4c/6-3c/6=1c/6=1/6c
znak / to dzielenie
