Calcul mental
n°28
“Des proportions ”
Calculer lesCalculer les
deux tiersdeux tiers
de 90.de 90.
Diapositive 1Diapositive 1
CalculerCalculer
5% de 70.5% de 70.
Diapositive 2Diapositive 2
Compléter :Compléter :
Diapositive 3Diapositive 3
=
9
...%
25
Compléter :Compléter :
Diapositive 4Diapositive 4
=
3 21
7 ...
Compléter :Compléter :
Diapositive 5Diapositive 5
=
20 ...
5 7
FIN
CORRECTION
Diapositive 1Diapositive 1
× = × =
2
90 2 30
3
60
Diapositive 2Diapositive 2
× = ×
= =
5
5% 70 70
100
350
100
3,5
Diapositive 3Diapositive 3
×
=
×
= =
9 9 4
25 25 4
36
100
36%
Diapositive 4Diapositive 4
=
3 21
7 49
Diapositive 5Diapositive 5
= =
20
4
5
28
7

4-Cm28 15-16