If c varies directly as d-3, and if c=16 when d=7, find c when d=10

Given, c varies directly as d-3. So, the equation will be:

c= k(d-3) where k is constant of variation.

If c=16 when d=7. So, plug in these values in the above equation. Hence,

16=k (7-3)

16=k*4

16/4= k

k= 4

Now plug in k=4 in the above equation to get the equation of this variation.

c=4(d-3).

We need to find c when d=10. So, plug in d=10 in the above equation to get the value of c. So,

c =4(10-3)

=4*7

=28

So, c=28.

12/11c

or

12

c

11