There are three numbers of a.b.c. it is known that the sum of a and B is 123, the sum of B and C is 124, and the sum of a and B is 125. Then the average number of A.B.C is many

Because a + B = 123, B + C = 124, a + C = 125
SO 2 (a + B + C) = 372
It is concluded that (a + B + C) / 3 = 62

When abc0 and C0 are known, Y > 1

Y = (B / a) * x-C / A, the image passes through 123 quadrants, with
(B / a) > 0, and when abc0, there is (A / b) * y + C / b > 0, and when b > 0, there is ay + C > 0,
y> When a + B + C-C / a > (a + b) / a = 1 + B / A, and (B / a) > 0, there is
Y>1+b/a>1.
When x > 0, Y > 1

The legal IP address in the following options is: a.206.53.3.78 b.123.48.82.220, which is wrong? What is the reason for the error

All of them are right
1. The symbol in IP address must be ".";
2. The IP address consists of four parts. The first, second and fourth bits cannot be 0 or 225;
3. The IP address is a number from 0 to 225 and cannot exceed its range
Note: the length of IP address is 32-bit binary. For the convenience of management, it is divided into 4 segments, which are expressed in decimal digits. The range of each segment is 0-225

In the following four examples, the legal IP address is () a 190.220.5 B 206.53.3.78 C 206.53312.78 D 123.43.82.220
It's a single choice, I want to know how you distinguish!

The answer is: BD
IP address is composed of four decimal digits, and the range of each digit is 0-255
A is not enough for 4 digits
In the C option, 312 is more than 255
To sum up, only BD is consistent

There are three numbers of a.b.c. it is known that the sum of a and B is 123, the sum of B and C is 124, and the sum of a and B is 125. Then the average number of A.B.C is many