Question

4) Before mandatory school closures, memes about how tough teaching is/how we

Answer 1

Answer:

Initially, there were 50 memes.

Step-by-step explanation:

It is given that the number doubles daily.

Let the initial number = a

On 2nd day, the number = 2a

On 3rd day, the number = 2 $\times$ 2a

On 4th day, the number = 2 $\times$ 2 $\times$ 2a

and so on..

If we look closely, it is a Geometric Progression with

First term = a and

The common ratio, r = 2

Also, it is given that, 12th term:

$a_{12}=102400$

nth term of a GP is given as:

$a_n=ar^{n-1}$

So,

$a_{12}=a \times r^{12-1}\\\Rightarrow 102400=a \times 2^{11}\\\Rightarrow a=\dfrac{102400}{2^{11}}\\\Rightarrow a=\dfrac{102400}{2048}\\\Rightarrow a = 50$

Hence, the answer is, the initial number is 50.