4.
[tex]42 \div 2 = 21 \\ 81 \div 9 = 9 \\ 96 \div 3 = 32 \\ 72 \div 6 = 12 \\ 54 \div 9 = 6 \\ 88 \div 8 = 11 \\ 63 \div 9 \div 7 = 1 \\ 64 \div 8 \div 4 = 2 \\ 80 \div 5 \div 2 = 8[/tex]
5.
[tex]a) \: 48 \div 2 = 24 \\ 10 \div 2 = 5 \\ 12 \div 2 = 6 \\ 18 \div 2 = 9 \\ 22 \div 2 = 11 \\ \\ b) \: 12 \times 2 = 24 \\ 36 \times 2 = 72 \\ 40 \times 2 = 80 \\ 20 \times 2 = 40 [/tex]
[tex]c) \: 16 \div 4 = 4 \\ 88 \div 4 = 22 \\ 40 \div 4 = 10 \\ 44 \div 4 = 11 \\ 20 \div 4 = 5 \\ \\d) \: 16 \times 4 = 64 \\ 8 \times 4 = 32 \\ 12 \times 4 = 48 \\ 20 \times 4 = 80 \\ 10 \times 4 = 40 \\ \\e) \: 20 \times 10 = 200 \\ 40 \times 10 = 400 \\ 60 \times 10 = 600 \\ 50 \times 10 = 500 \\ 70 \times 10 = 700[/tex]
