1. Вычисли: 1) 5·6; 8·5; 5·4; 5·9+5; 7·5+6; 3·5+8; 4·8−30; 9·3−12; 9·4+5; 25:5+10; 24:3+11; 18:3+24. 2) 25−(24−8); 40−(13+8); 60−(27−4); 35−(13−9); 100−52; 100−65.

1)

1. 5·6 = 30; 8·5 = 40; 5·4 = 20.
2. 5·9 + 5 = 45 + 5 = 50; 7·5 + 6 = 35 + 6 = 41; 3·5 + 8 = 15 + 8 = 23.
3. 4·8 − 30 = 32 − 30 = 2; 9·3 − 12 = 27 − 12 = 15; 9·4 + 5 = 36 + 5 = 41.
4. 25:5 + 10 = 5 + 10 = 15; 24:3 + 11 = 8 + 11 = 19; 18:3 + 24 = 6 + 24 = 30.

2)

1. 25 − (24 − 8) = 25 − 16 = 9.
2. 40 − (13 + 8) = 40 − 21 = 19.
3. 60 − (27 − 4) = 60 − 23 = 37.
4. 35 − (13 − 9) = 35 − 4 = 31.
5. 100 − 52 = 48.
6. 100 − 65 = 35.

Ответ: 30, 40, 20, 50, 41, 23, 2, 15, 41, 15, 19, 30; 9, 19, 37, 31, 48, 35.