S=ab a=10 b=10*60%=6см S=10*6=60см
а=5,5 в=5,5*60%=3,3см S=5.5*3.3=17.15см
а)
1. 2 5/6 : 2 4/15 = 17/6 : 34/15= 17/6 * 15/34=5/4=1,25
2. 1,4*0,3=0,42
3. 1,25-0,42=0,83
4. -0,24:0,83=-24/83
б)
1. 2 5/14 - 1 4/21 = 2 15/42 - 1 8/42=1 7/42= 1 1/6
2. 4,2 : 1 1/6= 4 2/10:1 1/6= 4 1/5: 1 1/6=21/5:7/6=21/5*6/7=18/5=3,6
3. 8-3,6=4,4
в)
1. 5 7/20-4 6/35=5 49/140 - 4 24/140=1 25/140 = 1 5/28
2. 23,1: 1 5/28 = 231/10 : 33/28 = 231/10 * 28/33=98/5=19,6
3. 30-19,6=10,4
г)
1. 3 11/21-2 4/15 = 3 55/105 - 2 28/105 = 1 27/105 = 1 9/35
2. 13,2 : 1 9/35 = 66/5 : 44/35 = 66/5 * 35/44 = 21/2=10,5
3. 14-10,5=3,5
1)60*10:100=6 1)60*5.5:100=3.3
2)6*10=60(S) 2)3.3*5.5=18.15