1) 10, 11,12,...,99=89 numere
patrate perfecte={11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,75,79,81,83,85,87,89}
P=24/89
2) 125% din 32= ?
125/100 x 32 =125:100 x 32
=1,25 x 32
=40
3) ?
4) ?
5) Fie x= numarul
x-16%x=(1-16%)x=1-16/100x=1-16:100=0,2x
0,2x = 434⇒x= 434:0,2⇒x= 434:2/10=434/1*10/2=4340/2
4340/2 se simplifica cu 2=2170 se simplifica cu 2=1085 se simplifica cu 5=217
x= 217
numarul=217
/=linie de fractie
*= inmultire