Răspuns:
ex.10
a=4
b=36
c=60
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ex.10
Explicație pas cu pas:
a=4
b= a x 9 = 4 x 9 = 36
a+b+c=100
4+36+c=100
c=100-4-36=100-40=60
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ex.11
a) 12 (123-23-70)=12x 30=360
b)12+23+289+8+11+17=360
c)321:3+42:6+42:7= 107+7+6=120
d)576;24-24=24-24=0
e)6754 x 100 -100x 6754 x 10=675 400-6 765 000= 6 078 600
sau
=100 x (6754 -6754x10 ) =100 x (6754-67540) =100 x ( -60786) = -6 078 600
f)65x 65 -45x 45=4225-2025=2200
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ex.12
a) (4+6 ): 2= 10/2=5
b) (3+5) :2= 8/2=4
c) (5+7+3) :3 =15/3=5
d) (4+6+5+9 ) :4 = 24/4=6
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ex.13
29+37 13+53
---------------- = -----------------
2 2
66 66
----- = --------
2 2
Coroana ?
