Ficha nº6-Multiplicação e divisão de nº inteiros

1-Calcula:

a)(+5) (+2)=                                   b)(+3) (+4)=                                   c)(+6) (+7)=

d)(+8) (+9)=                                  e)(+5) (+5)=                                  f)(+3) (+10)=

2-Calcula:

a)(+3) (-2)=                                   b)(-5) (+4)=                                   c)(-6) (+7)=

d)(+8) (-4)=                                   e)(-7) (+3)=                                   f)(-10) (+10)=

3-Calcula:

a)(-3) (-5)=                                    b)(-2) (-10)=                                  c)(-15) (-1)=

d)(-6) (-7)=                                    e)(-8) (-9)=                                    f)(-4) (-7)=

4)Calcula:

a)(+2) (+7)=                                  b)(-2) (-5)=                                    c)(-2) (+4)=

d)(+2) (-7)=                                   e)(-4) (-8)=                                    f)(-6) (+8)=

g)(-9) (-2)=                                    h)(+10) (-3)=                                 i)(+5) (-10)=

5)Utiliza a propriedade distributiva para desembaraçar de parêntesis e, depois calcula o valor de cada uma das expressões:

a)2 (3+5)=                                       b)-4 (8+2)=                                     c)-6 (-3+7)=

6)Põe em evidência o factor comum:

a)2 7+2 (-3)=                                               b)4 (-5)+4 8=                                              c)(-7) 2+(-7) 5=

d)2 4+2 (-1)=                                              e)7 (-1)+7 (-2)=                          f)-6 (+2)-6 (+1)=

7)Sem efectuar as multiplicações, averigua se o resultado é um nº positivo ou negativo:

a)(-2) (+1) (-5)=                                                                       b)(-3) 7 99=                               

c)(-5) (-7) (-10) (-3)=                                                         d)(-1) (-9) (-11)=

8)Identifica a propriedade que permite escrever:

a)-2 0=0                                                                                          b)1 (-25)=-25

c)-12 3=3 (-12)                                                                           d)-5 (7 2)=(-5 7) 2

e)-2 (10+22)=-2 10+(-2) 22                                                               f)(6-12) 4=6 4-12 4

9)Calcula:

a)(-8) (-4)=                                     b)6 (-2)=                                          c)10 (-5)=

d)(-14) (-7)=                                 e)(-20) 2=                                      f)15 (-3)=

10)Calcula:

a)-(2+6) (-2)-5=                                                                          b)(-3+7) (-2)+5=

c)12 (-4)+6 (-3)-(-10)=                                                           d)-3-(-30) 5 (-2)+1=

e)-5 (-1)-(-6) (-1)-(-2)=                                                         f)(-2-8 3) (-6 1+18)=

g)(2-2 (-9)) (-2-2 1)=                                                            i)13-(-20) 5+10 (-2) 2=

11)Calcula:

a)-3 2+1=                                                                                        b)-10+3 (-6)=

c)2 (-3)+6 3=                                                                                              d)-2 (-10+5)=

e)-3 (-8+2)+2=                                                                                             f)-2-3 (4-6)=

g)3-(6 3-10)=                                                                                 h)6 (-2-2)=

i)(10-0) (-3)=                                                                                j)(2-12) 10-2 (-3+4)=

l)12-3 (-6+2)=