Question

0,(2)·0,(27)·0,(2013)=0,(abcd) unde a,b,c,d sunt cifre in baza 10.Suma a+b+c+d este egala cu???

Answer 1

0,(2) = 2/9

0,(27) = 27/99

0,(2013) = 2013/9999

0,(2) x 0,(27) x 0,(2013) = 2/9 x 27/99 x 2013/9999 = 2/9 x 3/11 x 2013/9999 = 2/3 x 1/11 x 2013/9999 = 2/1 x 1/11 x 671/9999 = 2 x 1/1 x 61/9999 = 122/9999 = 0,(0122)

a+b+c+d = 0 + 1 + 2 + 2 = 5