1) x-4 1/2= -2 1/4
x= -2 1/4+4 1/2 =-9/4+9/2=(-9+19)/4=9/4
x=9/4
2) -x-6 4/5=3 1/2
-x=3 1/2+6 4/5 = 7/2+34/5=(35+68)/10=103/10=10 3/10
-x=10 3/10
x= -10 3/10
3) -x-11 1/2= -4 7/8
-x= -4 7/8+11 1/2 = -39/8+23/2=(-39+92)/8=53/8=6 5/8
-x=6 5/8
x= -6 5/8
Задание 4 :
а) 1/2 * x + 1/3 * x = 6
умножим все на 6
3x + 2x = 36 => 5x = 36 => x = 36/5
б) 1/5 * x + 1/3 * x = 15
умножим все на 15
3x + 5x = 225 => 8x = 225 => x = 225/8
Задание 5 :
мальчиков : 24 * 2/3 = 48/3 = 16
девочек 24 * 1/3 = 24/3 = 8
Задание 6 :
5 - 8 * (1 1/6 - 2/3) / 1 1/5 = 5 - 8 * (7/6 - 2/3) / (6/5) = 5 - 8 * (7/6 - 4/6) / (6/5) = 5 - 8 * 3/6 / (6/5) = 5 - 8 * 1/2 * 5/6 = 5 - 8/2 * 5/6 = 5 - 40/12 = 60/12 - 40/12 = 20/12 = 5/3