Question

Exercitiul 4
Va rog mult❤️

Answer 1

7/8*2/5=(7*1)/(4*5)=7*20

36/44*11/12=(6*1)/(4*2)=6/8=3/4

3 intreg 12/16*4/10=(3*16+12)/16 *4/10=60/16*4/10=6/4

2intreg1/4 *1 intreg23/45=(2*4+1)/4*(1*45+23)/45=9/4*68/45=17/9

Answer 2

$a) \frac{7}{8} \times \frac{2}{5} = \frac{7 \times 2}{8 \times 5} = \frac{14}{40} = \frac{7}{20}$

$b) \frac{36}{44} \times \frac{11}{12} = \frac{9}{11} \times \frac{11}{12} = \frac{9 \times 11}{11 \times 12} = \frac{99}{132} = \frac{3}{4}$

$c)3 \frac{12}{16} \times \frac{4}{10} = 3 \frac{3}{4} \times \frac{4}{10} = \frac{3 \times 4 + 3}{4} \times \frac{4}{10} = \frac{12 + 3}{4} \times \frac{4}{10} = \frac{15}{4} \times \frac{4}{10} = \frac{15 \times 4}{10 \times 4} = \frac{60}{40} = \frac{3}{2} = 1 \frac{1}{2}$

$d)2 \frac{1}{4} \times 1 \frac{23}{45} = \frac{2 \times 4 + 1}{4} \times 1 \frac{23}{45} = \frac{8 + 1}{4} \times 1 \frac{23}{45} = \frac{9}{4} \times 1 \frac{23}{45} = \frac{9}{4} \times \frac{1 \times 45 + 23}{45} = \frac{9}{4} \times \frac{45 + 23}{45} = \frac{9}{4} \times \frac{68}{45} = \frac{9 \times 68}{4 \times 45} = \frac{612}{180} = \frac{17}{5} = 3 \frac{2}{5}$