Question

please help me fast ​

Answer 1

7.)

A:B=2:3 = 10:15

B:C =5:6= 15: 18

A:B:C = 10:15:18

A = 10x

B = 15x

C =18x

A:C = 10x : 18x = 5:9

8) 3A=4B=5C

3A=4B=5C =k

3A =K

A =k/3

B =k/4

C =k/5

A:B:C = k/3:k/4:k/5= ⅓:¼:⅕

= 20/60 : 15/60: 12/60

= 20:15:12

9) A:B =3:4, B:C = 5:7

A:B = 15:20

B:C = 20:28

A:B:C = 15:20:28