Neil has already prepared 3 kilograms of dough and will continue preparing 1 kilogram of dough every hour. How many hours does Neil need to work to prepare 15 kilograms of dough? Let h, represent the hours and let d, represent the amount of dough made.

12 hours

Step-by-step explanation:

3+h=d

Simplify it to..

3+h=15

-3     -3

h=12

option 1 is correct.

step-by-step explanation:

y varies inversely with x and constant of variation is 4

the equation will be:

y = k/x

where k =4 so,

y = 4/x

if we put values of x of option 1 in the above equation and find values of y

y = 4/-2 => y =-2

y = 4/-1 => y = -4

y = 4/1 => y = 4

y = 4/2 => y =2

so, all the values of x and y are correct.

if we put values of x given in other options and find value of y we cannot find whole table satisfying the equation.

hence option 1 is correct.

the answer is 21%.