A) (3/8+3/5)*5/13= b) 4/7*35/36+1/2= c) 4 1/5:7/10 - 1/3= d) 12 1/9 - 1 1/4:1 7/8= e) (2 1/6 - 3/4):2/3= f) 2/5*1 2/3+4 2/3:7/9= g) (1/4+1/3)*(1/2-2/7)= h) (2 1/3-1 1/6):(1 1/3+1 1/6)= Jak by co to /jest kreska ulamkowa. Potrzebne na jutro.

2

Odpowiedzi

2009-12-15T17:31:21+01:00
A) (3/8+3/5)*5/13= (15/40+24/40)*5/13= 39/40*5/13= 3/8
b) 4/7*35/36+1/2= 5/9 + 1/2 = 10/18 + 9/18 = 1 1/18
c) 4 1/5:7/10 - 1/3= 21/5*10/7 - 1/3 = 6 - 1/3 = 4 2/3
d) 12 1/9 - 1 1/4:1 7/8= 12 1/9 - 1 5/17 = 12 1/9 - 2/3 = 12 1/9 - 6/9 = 11 4/9
e) (2 1/6 - 3/4):2/3= (26/12 - 9/12)*3/2 = 17/12*3/2 = 17/8 = 2 1/8
f) 2/5*1 2/3+4 2/3:7/9 = 2/5*5/3+ 8/3*9/7 = 2/3+ 3 3/7 =
14/21 + 72/21 = 4 2/21
g) (1/4+1/3)*(1/2-2/7)=(3/12+4/12)*(7/14-4/14)= 7/12*3/14= 1/8
h) (2 1/3-1 1/6):(1 1/3+1 1/6)=(7/3-7/6):(4/3+7/6)=
(14/6-7/6):(8/6+7/6)=7/6*6/15= 7/15
1 1 1
2009-12-15T17:49:06+01:00
A) (3/8+3/5)*5/13= (15/40+24/40)*5/13 = 39/40*5/13= 3/8

b) 4/7*35/36+1/2= 5/9+1/2=10/18+9/18=19/8= 1i 1/8

c) 4 1/5:7/10-1/3=41/5*10/7-1/3=82/7-1/3=246/21- 7/21=
=239/21=11 i 8/21

d) 12 1/9 - 1 1/4:1 7/8=109/9 -5/4 : 15/8=109/9 - 5/4 *8/15=
=109/9 -2/3= 109/9 - 6/9=103/9= 11 i 4/9

e) (2 1/6 - 3/4):2/3= (42/12 - 9/12): 2/3=33/12 * 3/2 =11/4 *3/2=
=33/8=4 i 1/8

f) 2/5*1 2/3+4 2/3:7/9= 2/5*5/3 +14/3 :7/9=2/3 + 14/3 *9/7=
=2/3 + 6= 6 i 2/3

g) (1/4+1/3)*(1/2-2/7)= (3/12+ 4/12)*(7/14-4/14)=
=7/12*3/14=1/8

h) (2 1/3-1 1/6):(1 1/3+1 1/6)=(7/3 - 7/6) : (4/3 +7/6)=
=(14/6 - 7/6):(8/6 + 7/6)= 7/6 : 15/6=7/6 * 6/15=7/15

C: sprawdziłam 2 razy ;)
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