1)20%=1/5
A=1/5B
B=5A
B=A+x=5A
x=4A
Ответ:на 400%
2.A=0.4B
B=0.3C
A=(0.4*0.3)C=0.12C
Ответ:12%
3.
A=0.15B C=0.4D
AC=0.15*0.4(B*D)=0.06BD
Ответ:6%
13 6/6 - 6 5/6 = 7 1/6
7 1/6 - 3/14 = 7 7/42 - 18/42 = 6 49/42 - 18/42 = 6 21/42 =6 1/2
+1 +2 +3 => 0.6х0.7х0.3=0.126
+1 +2 -3 => 0.6х0.7х0.7=0.294
+1 -2 +3 => 0.6х0.3х0.3=0.054
-1 +2 +3 => 0.4х0.7х0.3=0.084
ответ =0.578
+1 -2 -3 => 0.6х0.3х0.7=0.126
-1 +2 -3 => 0.4х0.7х0.7=0.196
-1 -2 +3 => 0.4х0.3х0.3=0.036
-1 -2 -3 => 0.4х0.3х0.7=0.126
Я незнаю я построил точку C с координатами (-1;-3) просто по другому не получается