should Julie accept her brother offer her brother says instead of paying her the 40$ he owes her, he will give her 2$ today and double the amount she has each day for 6 days. should Julie accept her brother's offer?

Respuesta :

Answer: The answer is yes.


Step-by-step explanation:  Given that Julie's brother owe $40 to her. He says instead of paying her this amount, he will give her $2 taday and double the amount she has each day for 6 days. We are to check whether Julie should accept the offer or not.

Now,

On 1st day, amount paid by Julie's brother = $2,

On 2nd day, amount paid by Julie's brother = $4,

On 3rd day, amount paid by Julie's brother = $8,

On 4th day, amount paid by Julie's brother = $16,

On 5th day, amount paid by Julie's brother = $32,

On 6th day, amount paid by Julie's brother = $64,

On 7th day, amount paid by Julie's brother = $128.

Therefore, these amounts will form a geometric sequence, where the first term, 'a' is 2 and the common ration, 'r' is 2. Number of terms is 7.

So, the total sum paid by Julie's brother in seven days is given by

[tex]S=2+4+8+16+32+64+128\\\\\Rightarrow S=\dfrac{2(2^7-1)}{2-1}=\dfrac{2\times 127}{1}=254>40.[/tex]

Hence, Julie should accept the offer.