If `a: 5 = b: 7 = c: 8`, then the value of `(a+b+c)/a=`

If a/3 = b/5 = c/7 , then value of (a+ b+c)/b will be:

If a^(3) = 1 + 7, 4^(2) = 1 + 5 + b , 5^(3) = 1 + 8 + c , then the value of a + b + c is

If a, b, c, d satisfy the equation a + 7b + 3c + 5d = 0 , 8a + 4b + 6c + 2d = - 16 , 2a + 6b + 4c + 8d =16 and 5a + 3b + 7c + d = -16 then the value of (a + d) (b + c) =______

If a/b=7/9,b/c=3/5 , then the value of a:b:c is

If (a + b) : (b + c) : (c + a) = 6 : 7 : 8 and (a + b + c) = 14, then the value of c is

If a = 4, b = -5, c = -8, find the value of (a+b) times c .

If a=7, b=5, c=3, then the value of a^2+b^2+c^2-a b-b c-c a i s -12 (b) 0 (c) 8 (d) 12