Question

Calculati.
A) 4supra5 : 12supra25=
B) 1supra12 - 1supra18=
C) 1,5+ 2supra3=
D) 4supra9 × 2,15=
E) (4- 2supra3): 5supra6=.

Answer 1

a)
$\frac{4}{5}: \frac{12}{25}= \frac{4}{5}* \frac{25}{12}$ =$\frac{5}{3}$

b) $\frac{1}{12}- \frac{1}{18}= \frac{18-12}{126}= \frac{6}{126}$=$\frac{1}{21}$

c) $\frac{15}{10}+ \frac{2}{3}= \frac{65}{30}= \frac{13}{6}$

d) $\frac{4}{9}* \frac{215}{100}= \frac{215}{9*25}= \frac{215}{225}$=$\frac{43}{45}$

e) $(4- \frac{2}{3}): \frac{5}{6}= \frac{12-2}{3}* \frac{6}{5}$=$\frac{10}{3}* \frac{6}{5}= \frac{2*2}{1}=4$

Answer 2

a) 4 supra5 (dupa regula) · 25 supra 12 (a doua inversata) egal (simplificam in crucis) cu 5 supra 3 ( scoatem intregul) 1 intreg si 2 supra 3
b) (aducem la numitorul comun)  3-2 supra lui 36 egal cu 1 supra 36
c) transformam numarul zecimal in fractie 15 supra 10+ 2 supra 3 egal(aducem la numitorul comun) 65 supra 30 egal cu 2 intreg si 5 supra 30
d) 4 supra 9 · 215 supra 100 egal cu 43 supra 45
e) (in paranteza aducem la numitorul comun) 10 supra 3 · 6 supra 5 egal cu 4