In addition, we know that a of 15 is 16, B of 17, C of 19 and D of 19 It is known that a of 15 = B of 16 = C of 17 = D of 19 1.A：B=（ ）；（ ）2.B：C=（ ）；（ ） 3.C：D=（ ）；（ ）4.D：A=（ ）；（ ）

In addition, we know that a of 15 is 16, B of 17, C of 19 and D of 19 It is known that a of 15 = B of 16 = C of 17 = D of 19 1.A：B=（ ）；（ ）2.B：C=（ ）；（ ） 3.C：D=（ ）；（ ）4.D：A=（ ）；（ ）

Suppose a = 15, B = 16, C = 17, d = 19
1.A：B=15:16
2.B：C=16:17
3.C：D=17:19
4.D：A=19:15

It is known that the sum of the three digit numbers is 23. There are several a, 12b, 14C, 15d and 17D in such a three digit number

5 9 9 (A33 divided by 2 = 3)
6 9 8 (A33=3X2X1=6)
7 9 7
7 8 8
6+3+3+3=15

It is known that 15% a = 16% B = 17% C = 19% d. find the following ratio a: B = B: C = C: D = D: a=

15 A = 16 b = 17 C = 19 D,
Find the following ratio
A:B= 15:16
B:C= 16:17
C:D= 17:19
D:A=19:15