Question

If (a + b): (b + c): (c + a) ::4:7:9
& a + b + c = 30 then find c = ?​

Answer 1

Step-by-step explanation:

(a + b): (b + c): (c + a) ::4:7:9

Therefore,

(a + b): (b + c)=4:7

7a+7b=4b+4c

7a+3b=4c............(i)

(9b+2c) +3b=4c [ putting 7a=9b+2c]

12b=2c

6b=c

b=c/6.......... (iii)

Now,

(b + c): (c + a)=7:9

9b+9c=7c+7a

9b+2c=7a..........(ii)

9c/6+2c=7a [ putting b=c/6]

21c/6=7a

a=c/2

Now,

a + b + c = 30

c/2+c/6+c=30

20c=30*12

c=30*12/20

c=18

Answer 2

Answer:

Step-by-step explanation: