CHRONO

-INF s.

Ajouter ou soustraire des dizaines entières.

CHRONO

0 s.
40 + 10 =
40 = 20 +
30 + 60 =
10 + 30 =
40 = 10 +
70 = 10 +
50 + 40 =
80 - 10 =
50 = 20 +
60 - 10 =
20 + 50 =
20 - 10 =
20 + 70 =
30 = 10 +
80 = 60 +
60 = 50 +
90 = 60 +
60 + 20 =
60 + 20 =
80 - 70 =