If D varies directly with t and D is 105 when t is 3 then value of D when t is 8 is equal to 280
Solution:
In this sum we have been given that there is a direct relationship between d and t.
If d is 105 when t is 3 so now, we need to find d when t is 8.
To do this we can simply use the unitary method. The definition of unitary method is, the unitary method is a technique for solving a problem by first finding the value of a single unit, and then finding the necessary value by multiplying the single unit value.
Now, according to the definition we need to find the value of d when t is 1.
This can be done as follows:
[tex]D=\frac{105}{3}=35[/tex]
Therefore, the value of d when t = 1 is 35.
Now, if the value of t=8 then d becomes:
[tex]D=35 \times 8=280[/tex]
Hence, when t=8 the value of d is 280.