Răspuns:
Explicație pas cu pas:
2.
a)
3/4*(2/5 + 7/3) = 3/4*(6/15 + 35/15) = 3/4*41/15 = 41/20
3/4*(2/5 + 7/3) = 3/4*2/5 + 3/4*7/3 = 3/10 + 7/4 = 6/20 + 35/20 = 41/20
b)
2/5*(3/4 + 5/8) = 2/5*(6/8 + 5/8) = 2/5*11/8 = 11/20
2/5*(3/4 + 5/8) = 2/5*3/4 + 2/5*5/8 = 3/10 + 1/4 = 6/20 + 5/20 = 11/20
c)
rezolva singur; ai doua modele
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3.
a)
2/3*1/5 + 2/3*4/5 = 2/15 + 8/15 = 10/15 = 2/3
2/3*1/5 + 2/3*4/5 = 2/3*(1/5 + 4/5) = 2/3*5/5 = 2/3
b)
4/7*5/3 + 4/7*2/3 = 20/21 + 8/21 = 28/21 = 4/3
4/7*5/3 + 4/7*2/3 = 4/7*(5/3 + 2/3) = 4/7*7/3 = 4/3
d)
11/6*9/8 - 11/6*3/8 = 99/48 - 33/48 = 66/48 = 11/8
11/6*9/8 - 11/6*3/8 = 11/6*(9/8 - 3/8) = 11/6*6/8 = 11/8
c); e); f)
rezolva singur; ai trei modele
