А қандай сан ,4-тен есе кіші

А)

546 =500+40+6 454 =400+50+4 546+454=500+400+40+50+6+4=900+90+10=1000

146+66+54+34=(146+54)+(66+34)=300

248+(352+236)=(248+352)+236=600+236=836

А) 1,8+3           1,6:4                  2,1:3                       3,6:9
Ә) 6,9+3,          4,8:4                  6,6:6                       8,2:2
Б) 6,5+5,           5,2-4                 9,1:7                        8,4:6
В) 7,5+3,           9,8:2                 5,4:2                        9,6:4
Г) 3:5,              4:5                     7:5                           7:2

а) қандай сан 2,4-тен 2 есе кіші?