Пошаговое объяснение:
1)Площадь круга равна S= пR^2= 3,14*30^2=2826 см2
2) 5/9 * 3/25 = 1/15
5 1/ 5 : 2 2/15 = 26/5 * 15/32= 65/18= 3 11/18
2 1/8+3 1/4= 17/8+ 13/4=17/8+26/8=43/8= 5 3/8
4 1/6-2 1/3= 25/6- 7/3=25/6-14/6=11/6= 1 5/6
(3 3/8 - 2 1/3) : 1 1/4 = (27/8-7/3) *4/5= (81/24-56/24)*4/5= 25/24*4/5= 5/6
3) 8/x=2/7
2х= 8*7
2х= 56
х = 28
1,2/6= 3/х
1,2х=6*3
1,2х= 18
х= 15
Пошаговое объяснение:
1)Площадь круга равна S= пR^2= 3,14*30^2=2826 см2
2) 5/9 * 3/25 = 1/15
5 1/ 5 : 2 2/15 = 26/5 * 15/32= 65/18= 3 11/18
2 1/8+3 1/4= 17/8+ 13/4=17/8+26/8=43/8= 5 3/8
4 1/6-2 1/3= 25/6- 7/3=25/6-14/6=11/6= 1 5/6
(3 3/8 - 2 1/3) : 1 1/4 = (27/8-7/3) *4/5= (81/24-56/24)*4/5= 25/24*4/5= 5/6
3) 8/x=2/7
2х= 8*7
2х= 56
х = 28
1,2/6= 3/х
1,2х=6*3
1,2х= 18
х= 15