Question

A machine called Feynman, produces output, that is 5 times its input followed by an increase of 2. Another machine called Maxwell, produces output, that is 5 times its input followed by a decrease of 2. The output of Feynman feeds into Maxwell. If Maxwell produces an output of 33, the input to Feynman must be:
(a). 1
(b). 31/5
(c). 41/25
(d). 21/25

Answer 1

I honestly think that the answer is a

Answer 2

Answer:

Option: a is the correct answer.

                (a)  1

Step-by-step explanation:

• Let the input of Feynman be denoted by  i and it's output be denoted by f.

              Now, it is given that:

Feynman, produces output, that is 5 times its input followed by an increase of 2.

i.e. the equation that will be formed using this information is:

                  $f=5i+2------------(1)$

• Also, it is given that:

The output of Feynman feeds into Maxwell.

Let the output of Maxwell be denoted by m and it's input is f.

Maxwell, produces output, that is 5 times its input followed by a decrease of 2.

This means that the equation that will be formed using this information is:

             $m=5f-2----------------(2)$

Now, we put the value of f from equation (1) into equation (2)

i.e.

$m=5(5i+2)-2\\\\i.e.\\\\m=25i+10-2\\\\i.e.\\\\m=25i+8$

If the output of Maxwell is: 33

i.e.

$m=33$

Then

$33=25i+8\\\\i.e.\\\\25i=33-8\\\\i.e.\\\\25i=25\\\\i.e.\\\\i=\dfrac{25}{25}\\\\i.e.\\\\i=1$

Hence, the input of Feynman is: 1