Question

Calculeaza adaugand fractiile la firma ireductibila si grupând convenabil termenii:a) 23 supra 69 + 12 supra 36+ 18 supra 58 b) 10supra 26+18supra12+24supra39+5supra10 c) 1•2supra3•4 + 4•3supra 3² • 5 + 2•3•5 supra 2²• 3² .

Answer 1

a) 
23/69 + 12/36 + 18/58 = 1/3 + 1/3 + 9/29 = 2/3 + 9/29 = 58/87 + 27/87 = 85/87

b)
10/26 + 18/12 + 24/39 + 5/10 = 5/13 + 3/2 + 8/13 + 1/2 =

= (5/13 + 8/13) + ( 3/2 + 1/2) = 

= 13 /13 + 4/2 = 

= 1 + 2 =

= 3 

c) 
(1 × 2 × 4 )/3 + ( 4 ×3 ) ×5 / 3 ² + ( 2 ×3 × 5) / ( 2² × 3²) =

= 8/3 + 20/3 + 5/ 6 =

= 16/6 + 40/6 + 5/6 =

= 61/60 =

= 1 intreg si 1/60