Mental maths. Simple level exercises. Яна Малова
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6 SECTION (DOUBLE FIGURES 20+, +20)
17+20 =
19+20 =
21+20 =
6+20 =
20+7 =
7+20 =
9+20 =
20+2 =
20+6 =
20+8 =
20+10 =
20+16 =
20+57 =
20+1 =
20+58 =
20+18 =
20+19 =
18+20 =
20+20 =
20+28 =
8+20 =
20+29 =
20+50 =
20+17 =
22+20 =
20+51 =
20+52 =
20+53 =
20+78 =
20+9 =
20+54 =
20+56 =
20+77 =
20+62 =
5+20 =
20+68 =
20+24 =
20+72 =
20+12 =
20+75 =
56+20 =
20+79 =
27+20
69+20 =
1+20 =
20+23 =
3+20 =
77+20 =
65+20 =
20+59 =
4+20 =
10+20 =
20+67 =
76+20 =
20+55 =
20+71 =
20+3 =
20+4 =
20+5 =
15+20 =
16+20 =
2+20 =
20+76 =
23+20 =
28+20 =
29+20 =
50+20 =
63+20 =
20+64 =
20+66 =
24+20 =
51+20 =
20+22 =
20+25 =
71+20 =
20+27 =
72+20 =
53+20 =
20+61 =
74+20 =
20+65 =
55+20 =
26+20 =
20+11 =
20+13 =
20+63=
20+15 =
57+20 =
58+20 =
20+70 =
59+20 =
11+20 =
12+20 =
13+20 =
20+60 =
14+20 =
20+69 =
20+74 =
25+20 =
60+20 =
67+20 =
20+73 =
61+20 =
73+20 =
20+14 =
20+21 =
62+20 =
20+26 =
64+20 =
52+20 =
79+20 =
54+20 =
66+20 =
68+20 =
70+20 =
75+20 =
78+20 =