Question

- what number should be added to each of 7, 17, 22 and 47 so that the resulting numbers will be in proportion in the given order? options:

Answer 1

if 3 is added then num will be...10,20,25,50...

Answer 2

Answer:  The required number to be added is 3.

Step-by-step explanation:  We are given to find the number that should be added to each of 7, 17, 22 and 47 so  that the resulting numbers will be in proportion in the given order.

Let x be the required to be added.

Then, according to the given information, we must have

$(7+x):(17+x)=(22+x):(47+x)\\\\\\\Rightarrow \dfrac{7+x}{17+x}=\dfrac{22+x}{47+x}\\\\\\\Rightarrow (7+x)(47+x)=(22+x)(17+x)\\\\\Rightarrow 329+54x+x^2=374+39x+x^2\\\\\Rightarrow 54x-39x=374-329\\\\\Rightarrow 15x=45\\\\\Rightarrow x=\dfrac{45}{15}\\\\\Rightarrow x=3.$

Thus, the required number to be added is 3.