Question

Fara a efectua calculul , stabiliti numarul de zecimale ale rezultatului :a) 2,3×731= b) 2,3×2,71= c) 7,9 ×1,7= d) 1,721×3,29= e) 9,007×2,4= f) 1,71×2,44071= 2) efectuati . 5/21: 15/28= b) 3si 4/17:55/51= c) 1/7:3/5 totul supra 3/7 ori 5/6

Answer 1

a) 2,3×731=   1 zecimala
b) 2,3×2,71 =  3 zecimale
c) 7,9 ×1,7=    2 zecimale
d) 1,721×3,29=    5 zecimale
e) 9,007×2,4=    4 zecimale
f) 1,71×2,44071=   7 zecimale

2)  
a) 5/21: 15/28= 5/21×28/15=1/3×4/3=4/9=0,(4)
b) 3si 4/17:55/51= 55/17 × 51/55 =3
c) (1/7:3/5 ) /( 3/7 ori 5/6) =(1/7×5/3 ) /( 3/7 × 5/6) =(5/21) /( 5/14) =
=5/21×14/5=2/3