1) 8 /27×9/7÷4/7 =8/27*9/7*7/4=2/3
2)11/12÷7/24÷2 2 / 21 =11/12*24/7*21/44=6/4=1 1/2
3) 2 2/3÷24/35÷2 7/9 =8/3*35/24*9/25=7/5=1 2/5
4) 13 1/2×1 1/2÷2 1/4 =27/2*3/2*4/9=9
5)15/16÷5/8×1 1/9=15/16*8/5*10/9=5/3=1 2/3
6)13/14÷1 4/21÷13/5=13/14*21/25*5/13=3/10
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13м2 = 1300дм2
27дм2=2700см2
48040 ар=480га 40 ар
4800 дм2=48м2
1000см2=10дм2
Периметр: 290см
Площадь: 3000см2
#1)-2
#2)5/6 * 3/5 = 1/2( или 0,5)
8/9 : 4/3 = 8/9 * 3/4 =2/3
5/3 * 6/25 : 8/5 = 2/5 : 8/5= 2/5 * 5/8 =2/8= 1/4
#3)2/3:7/12*(4-1 7/8)+1 5/6=
=2/3*12/7*(3 7/8)+1 5/6=
=8/7*3 7/8+1 5/6=
=8/7*31/8+1 5/6=
=31/7+1 5/6=
=3 3/7 + 1 5/6=
=3 18/42 + 1 35/42=
=4 53/42= 5 11/42