1) (2 3/25+9,6-5,72):0,15/10,92:(2,6*0,5)-0,4==(53/25+9,6-5,72):0,15/10,92:1,3-0,4==(2,12+9,6-5,72):0,15/8,4-0,4==6:0,15/8=40/8=5
2)4 2/3-5/9*2 4/7/(2 1/7+1 2/3):5+0,8*1,25==14/3-5/9*18/7/(15/7+5/3):5+1==14/3-10/7/((15*3+5*7)/21):5+1==((14*7-10*3)/21)/(80/21):5+1=(68/21)/16/21+1=(68/21)/(16/21+21/21)==(68/21)/(37/21)=68/37=1 31/37
8- 3 3/4*(1 1/2-3/5)/6=7 7/16
1.1 1/2- 3/5=9/10
2.9/10:6=3/20
3.3 3/4*3/20=9/16
4.8-9/16=7 7/16
1) Число 25 . ( 25+27)=52 . 52 -25=27.
9ч-4ч33мин=20ч33мин наверна так
С=2πr = 2*3.14*5 = 31.4 cм
S=πR² = 3.14 * 5² = 3.14 * 25 = 78.5 см²
С=πД = 3,14*721,98 дм
S=πR² = π*(Д/2)² = 3,14 * (7/2)² = 3,14 * 12,25 = 38,465 дм²
С=π*Д ⇒Д=С/π = 37,2 : 3,14 = 11,847 см
С=2πR ⇒R=C/2π = 37,2:(2*3,14) = 37,2 : 6,28 = 5,92 см²