Question

I checked full internet and even brainly and found no answer to this question. please answer it .​

Answer 1

Let us assume $x$ as a number of families owning either 2 or 6 cows.

According to the question,

$\boxed{\begin{aligned}&\text{The number of families with 2 cows}: x\\\\&\text{The number of families with 4 cows}: 20-2x\\\\&\text{The number of families with 6 cows}: x\end{aligned}}$

The total number of cows are,

$\begin{aligned} \cdots \longrightarrow 2x+4(20-2x)+6x&=2x+80-8x+6x\\\\&=(2-8+6)x+80\\\\&=80 \end{aligned}$

Hence, there are $\underline{80}$ cows in total. Option d. is the right answer.